The Effects of Substitution on the Optical Properties of poly(p-phenylenevinylene) Derivatives.
ISBN Number: 978-979-8575-05-1
P R OC E E D I N G
THE 2nndd
INTERNATIONAL CONFERENCE ON
OPTICS AND LASER APPLICATIONS
ICOLA’07
Yogyakarta, INDONESIA
September 5-7, 2007
Organized by:
The Study Program on
Opto-Electrotechniques and Laser Applications
Dept. of Electrical Engineering, University of Indonesia
Indonesia Section
ISBN Number: 978-979-8575-05-1
PROCEEDING
THE 2nndd
INTERNATIONAL CONFERENCE ON
OPTICS AND LASER APPLICATIONS
ICOLA’07
Yogyakarta, INDONESIA
September 5-7, 2007
Indonesia Section
Organized by:
The Study Program on
Opto-Electrotechniques and Laser Applications
Dept. of Electrical Engineering, University of Indonesia
i
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The Study Program on Opto-Electrotechniques and Laser Applications
Dept. of Electrical Engineering, University of Indonesia
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ii
Preface
Dear the ICOLA 2007 Participants
On behalf of the Committee of International Conference on Optics and Laser Applications, ICOLA’07
allow me to express my gratitude to all of you, who participate in this conference. The Study Program on
Opto-Electrotechniques and Laser Applications, Dept. Electrical Engineering, University of Indonesia
organizes this conference in conjunction with the 30th anniversary of the study program.
The ICOLA’07 is technically supported by the International Commission for Optics (ICO), International
Society for Optical Engineering (SPIE), and the Abdul Salam International Center for Theoretical
Physics (ICTP), in cooperation with other professional society like: HFI, HAI, IEEE Indonesia Section,
etc. We would like to warmly welcome the participants from USA, Japan, South Korea, P.R. China,
Taiwan, Thailand, Singapore, Malaysia, Bangladesh, India, Iran, Yemen, Algiers, Moldova, Ukraine, the
Netherlands, etc., especially the distinguished professors from the well known and recognized
institutions as invited speakers.
The time of conference is remarked by a significant progress in science and technology, especially in
the field opto-electronics and laser applications. Although our country is facing with political and
economical problems, in fact, there are still some researchers, young engineers, students --who are
working in their own fields-- wishing to present their works in this conference.
We received around 81 extended abstracts (invited, overseas, and domestic) but only about 55 selected
or reviewed papers will be presented in the conference. These are divided into three categories:
A: Nanotechnology, Biomedical Optics, and Optical Communication
B: General Optics, Holography, and Laser Technology
C: Photonic Devices/Materials, Design, and Applications
We would like to thank to all Committee members, to all organizations and sponsors who have provided
their supports and efforts to make this conference become a success. In addition, thanks also are
forwarded to all individuals for their valuable time and supports to the conference.
Finally, have intensive discussions in the conference and enjoyable stay in Yogyakarta !
Prof. Dr. Sar Sardy
General Chairman of ICOLA2007
iii
ICOLA2007 Committee Members
Organizer
The Study Program on Opto-electrotechnique and Laser Applications (OEAL)
Department of Electrical Engineering, Faculty of Engineering, University of Indonesia
Sponsor (technical)
ICO, SPIE, ICTP, IEEE Indonesia Section, Indonesian Physical Society, Indonesian Astronomical Society
International Program Committee
Prof. Dr. Suganda Jutamulia, Chair, Univ. of Nothern California, USA
Prof. Dr. Yashuhiru Suematsu, The Past President Tokyo Institute of Technology
Prof. Dr. Jumpei Tsujiuchi, Prof. Emeritus Tokyo Institute of Technology
Prof. Dr. Toshimitsu Asakura, Prof. Emeritus Hokkaido University
Prof. Dr. Guoguang Mu, Nankai University, China
Prof. Dr. Lambertus Hesselink, Stanford Univ. USA
Prof. Dr. Mohammad S. Alam, Univ. of South Alabama, USA
Prof. Dr. Francis Yu, Pennsylvania State University, USA
Prof. Dr. Cardinal Warde, Massachusetts Inst. Tech. USA
Prof. Dr. Pochi Yeh, Univ. of California Santa Barbara, USA
Prof. Dr. Alexander Sawchuck, SIPI, Univ. of Southern California, USA
Prof. Dr. Kehar Singh, Indian Inst. Tech. Delhi, India
Prof. Dr. Rene Dandliker, President SATW, Switzerland
Prof. Dr. Gallieno Denardo, ICTP, Trieste, Italy
Prof. Dr. Min Gu, Swinburne Univ. of Technology, Australia
Prof. Dr. Arthur Chiou, National Yang Ming Univ., Taiwan
Prof. Dr. Joewono Widjaja, Suranaree Univ. of Technology, Thailand
Prof. Dr. Anand Krishna Asundi, Nanyang Technological Univ. Singapore
Prof. Dr. Yoshizumi Yasuda, Tokyo University for Information Science, Japan
Prof. Dr. Yoshihisa Aizu, Muroran Inst. Tech. Japan
Prof. Dr. Byoung Yoon Kim, Novera Optics, KT Second Research Center, South Korea
Prof. Dr. Feijun Song, China Daiheng Coorp., P.R. China
Prof. Dr. Kazuhiko Ohnuma , Chiba University, Japan
Prof. Dr. A.N. Chumakov, National Academy of Science, Belarus
Dr. Yoshiji Suzuki, Hamamatsu Photonics KK, Japan
Advisory Committee
Prof. Dr. Rinaldy Dalimi, Chair, Dean Fac. of Engineering, University of Indonesia
Prof. Dr. Eko Tjipto Rahardjo, University of Indonesia
Prof. Dr. Bambang Hidayat, Chairman Indonesian Academy of Science
Prof. Dr. Zuhal, President Indonesian Al-Azhar University
Prof. Dr. Budi Santoso, Indonesian Atomic Energy Agency
Prof. Dr. Tjia May On, Bandung Institute of Technology
General Chairman
Sar Sardy, Professor, Head of OEAL-FTUI, Univ. of Indonesia
Technical Program Committee
Dr. Gunawan Witjaksono, Chair, University of Indonesia
Prof. Dr. Dadang Gunawan, IEEE-Indonesia Section
iv
Prof. Dr. Anung Kusnowo, Indonesian Institute of Science
Dr. Ary Syahriar, Indonesian Al-Azhar University
Dr. Henri Putra Uranus, University of Twente, the Netherlands
Dr. Ir. Sekartedjo, Sepuluh Nopember Institute of Technology
Dr. Hendrik Kurniawan, University of Indonesia
Prof. Dr. Masbach R. Siregar, Indonesian Physical Society
Dr. Hakim L. Malasan, Indonesian Astronomical Society
Local Organizing Committe
Dr. Ir. Purnomo Sidi Priambodo, MSEE, Chair, University of Indonesia
Dr. Ir. Dodi Sudiana, MEng, University of Indonesia
Dr. Ir. Retno Wigajatri MEng, University of Indonesia
Dr. Abdul Muis, ST. MEng, University of Indonesia
Dr. Ir. Feri Yusivar, MEng, University of Indonesia
Fitri Yuli Zulkifli, ST. MSc, University of Indonesia
Arief Udhiarto, ST. MT, University of Indonesia
Budi Sudiarto, ST. MT, University of Indonesia
Muhammad Suryanegara, ST. MSc, University of Indonesia
F. Ashta Ekadiyanto, ST. MSc, University of Indonesia
Aji Nur Widyanto, ST, University of Indonesia
v
CONTENT
Invited-Planery Papers
Scientists and Their Society: Between Advocacy and Arbitration
1
Bambang Hidayat
Angular Division Multiplexing in Pulsed Digital Holography for
Recordings of High Resolution
7
Hongchen Zhai, Xiaolei Wang, CaojinYuan and Guoguang Mu
Design and analysis for laser beaming devices using surface plasmon
resonance
12
Byoungho Lee, Hwi Kim, and Seyoon Kim
Phase Singularity Distribution of Fractal Speckles
17
Jun Uozumi
Laser Aided Golf Trainer – Product and Business Development
22
Suganda Jutamulia
Quality of Images Reconstructed from In-Line Fresnel Holograms
25
Joewono Widjaja and Phacharawadee Raweng
Three-dimensional computer-generated holographic display of
biological tissue
30
Toyohiko Yatagai Yusuke Sando , Ken-ichi Miura and Masahide Itoh
,
Application of VIS-NIR Spectral Imaging to Skin Tissue
Measurements
34
Yoshihisa Aizu, Takaaki Maeda, and Izumi Nishidate
On-demand optical tweezers by time-division multiplexing of
computer-generated holograms
39
Toshiaki IWAI and Johtaro YAMAMOTO
Digital holography a new paradigm for imaging, microscopy
and measurement
43
Anand Asundi and Vijay Raj Singh
Encrypted Content-addressable Holographic Memories
Kehar Singh, Renu John, and Joby Joseph
vi
48
Three-Dimensional Microscopic Imaging
53
Colin J.R. Sheppard
Contributed Papers : Overseas
Enhancing the Performance of Integrated Optical Sensor by
Slow-light: Theoretical Study on Ring-Resonator Based Structures
56
Henri P. Uranus, and Hugo J. W. M. Hoekstra
Electro-Optical Studies Of Chemically Deposited Znxcd1-X
Nanocrystalline Films
61
Shashi Bhushan and Ayush Khare
Compact Optical Sensor for Soil Nutrients Analysis by using LEDs
66
Masayuki Yokota
Precision Dynamic Force Measurement Using Mass Levitation and
Optical Interferometer
70
Yusaku FUJII
Optical properties of vanadium doped ZnTe thin cermet films for
selective surface applications
74
M. S. Hossain, R. Islam and K. A. Khan
Improved 90° Bend Transmission Defined in a Triangular Lattice
Photo nic Crystals
79
Leila DEKKICHE, and Rafah NAOUM
Dual Ball Lenses for Relaxed Alignment Tolerances in Pigtailing of a
Laser Diode Transmitter
83
Mohamed Fadhali, Saktioto,Jasman Zainal, Yusof Munajat, Jalil Ali and Rosly Abdul Rahman
Normalized Frequency Gradient of Coupled Fibers as a Function of
Coupling Ratio
88
Saktioto, Jalil Ali, Jasman Zainal, Mohamed Fadhali
Experimental studies on the short wave transmission characteristics of
a laser protection filter coating used in the laser optical systems
93
Nimmagadda Rama Murthy, and A.S. Murthy
Two-Photon Lasing Controlled by Resonator Losses
98
Vitalie Eremeev, Marina Turcan, Nicolae Enaki
Incoherent Light Depolarization by Multiple Reflections
Yaroslav Aulin
vii
103
Influence of Filters on Recognition of Noisy Objects
107
Seyed Mohsen Mirsadri, Hosein Bolandi, Farhad Fani Saberi
Design and Development of Holographic Sighting System used for
small arm weapons in Close Quarter Battle situations
113
Nimmagadda Rama Murthy, P.Rajesh Kumar, and N. Raghavender
Contributed Papers : Domestic
The Effects of Substitution on the Optical Properties of
poly(p-phenylenevinylene) Derivatives
117
A. Bahtiar and C. Bubeck
Possible use of formaldehyde as fluorescence tracer to examine the
state of mixture formation in Spark Ignited (SI) engines
122
A.M.T Nasution1, V. Beushausen, R. Mueller
The Parameter Modeling of Grating Reflector for External Cavity
Tunable Lasers as light sources in DWDM System
127
Supriyanto
Surface Roughness Measurement by Electronics Speckle Pattern
Interferometry (ESPI) Method
131
A.S. Pramono, Rakiman, D. Ardiansyah , H. Setijono
Generalized Linear Dispersion Relation for Symmetrical
Directional-coupler of Five-layer Waveguide
135
Sekartedjo, and Ali Yunus Rohedi
Design of Multimode Interference Structure for 1x2 Optical
Waveguide Filter for 1.3 and 1.55 µm
140
Sekartedjo, and Agus Muhamad Hatta
Phase Unwrapping Applied to Digital Holography
143
D. Ardiansyah and Sekartedjo
Introducing Stable Modulation Technique for Solving an
Inhomogeneous Bernoulli Differential Equation
147
Ali Yunus Rohedi
High Temperature Annealing effects on Silica based Optical
Waveguides
Ary Syahriar
viii
152
Simple Model of Design 1.55μm and 1.31μm VCSEL’s for High Speed
Modulation Optical Interconnections
158
Gunawan Witjaksono, Ucuk Darusalam, Gunady Haryanto, Arum Setyowati
Simulation GaInAsP/InP Surface Emitting Distributed Feedback
Laser for Radio Over Fiber Application
163
Gunawan Witjaksono, Irma Saraswati
Optical Waveguide Directional Fiber Coupler Design Method Based
on Numerical Analysis
167
Ucuk Darusalam, Gunady H., Arum Setyowati, Purnomo Sidi Priambodo, V. Vekky R. R
Gain Characteristics Analysis of Distributed Raman Amplifier on
CWDM Band Based on Numerical Simulation
172
V. Vekky R. Repi, Ucuk Darusalam, Purnomo Sidi Priambodo
Design of Multimode Interference (MMI) Couplers Using Method of
Lines
177
Helmi Adam, Ary Syahriar
Design of Three Parallel Waveguide Using Coupled Mode Theory and
Method of Lines
Helmi Adam, Dwi Astharini, Ary Syahriar
181
Laser Micromachining of Silicon and Its Application for the
Fabrication of Micro Gas Sensor Device
185
Goib Wiranto,Gandi Sugandi, I Dewa P. Hermida, and Edy Supriyanto
Edge-element based finite element analysis of leaky modes of photonic
crystal microcavities
189
Ardhasena Sopaheluwakan
Measurement of the nonlinear susceptibility of the third order
dielectric materials by means of Z-scan technique
193
Freddy Susanto Tan
Optical Fibre Biosensor Based on Enzymatically Doped Sol-Gel
Glasses for Monitoring of Pesticides in Flow System
197
Bambang Kuswandi, Chulaifah Indah Fikriyah, Agus Abdul Gani and Anak Agung Istri
Ratnadewi
Simulations of rib waveguide structure with trapezoidal cross-section
using Finite Difference Method
Suwasti Broto, N. Mohd Kassim, M.H. Ibrahim
ix
202
Achieving gain flatness in C-band Erbium Doped Fiber
Amplifiers
207
Sholeh Hadi Pramono, Sar Sardy, Ary Syahriar, Irwan R.Hc, Sasono R
Design and Implementation of Knowledge-Based Expert Systems GIS
for Fishing Ground Prediction Models: a preliminary results
210
Muhamad Sadly, and Yoke Faisal
The Assessment of Fish Abundance by using Modis Satellite Data of
SSC and SST (Case Study : In the South Kalimantan)
214
Suhendar I Sachoemar, Muhamad Sadly and Fanny Meliani
Fitting of Linear Transducer Characteristic using Genetic Algorithm
and Segmented by Golden Ratio
Purwowibowo, Sar Sardy, and Wahidin Wahab
219
Visible to Near Infrared Spectrum
Reflectance Ratios in Cancer Detection
224
Hamdani Zain, Anwar S. Ibrahim, Aryo Tedjo and Kusmardi
Speech Recognition for Controlling Movement of the Wheelchair
227
Thiang
A Comparison of Discrete Cosine Transform and Discrete Wavelet
Transform Techniques in Audio Compression
232
Endra
Face Identification with Multi-resolution Method
235
Indra Riyanto, and Wihartini
Splice Loss: Estimated Value Versus OTDR Measurement
238
Dwi Bayuwati, Tomi Budi Waluyo, Imam Mulyanto
The Spectral Reflectance Characteristic of Coral and Its Relation to
The Optic Properties of Waters
242
Nurjannah Nurdin, Muhamad Sadly, Indra Jaya, Vincentius Siregar
Introducing “OPTO”: Portal for Optical Communities in Indonesia
Tomi Budi Waluyo and Laksana Tri Handoko
x
245
Proc. of the 2nd International Conf. on Optics and Laser Applications
ICOLA’07, September 5-7, Yogyakarta, Indonesia
The Effects of Substitution on the Optical Properties of
poly(p-phenylenevinylene) Derivatives
A. Bahtiar* and C. Bubeck†
*
Department of Physics, University of Padjadjaran Bandung, Jl. Jatinangor km. 21 Sumedang, 45363, Indonesia.
Tel. ++62-22-7796014, Fax. ++62-22-7792435, email: ayibahtiar@yahoo.com
†
Max Planck Institute for Polymer Research, Ackermannweg 10, D-55128 Mainz, Germany
Tel. ++49-6131-379122, Fax. ++49-6131-379100, email: bubeck@mpip-mainz.mpg.de
Abstract - We have studied the optical linear, optical
nonlinear and waveguide properties of thin films of
newly synthesized poly(phenylenevinylene) (PPV)
derivatives: MEH-PPV, M3EH-PPV and copolymer
MEH-M3EH-PPV by means of reflectrometry, prism
coupling, third harmonic generation spectroscopy
and waveguide propagation loss. Anisotropic
refractive index measurements by means of
waveguide prism coupling and reflectometry were
used to analyse the polymer chain orientation in the
films. We observed that the absorption coefficient,
refractive index, birefringence and third order
susceptibility and waveguide loss coefficient are
increased in going from MEH-PPV, MEH-M3EHPPV and finally to M3EH-PPV, which indicates that
the thin film of M3EH-PPV have the most polymer
chain segments oriented parallel to the film plane. For
all-optical switching applications, the thin film of
MEH-PPV is the most appropriate candidate, since it
exhibit a good combination of large value of cubic
nonlinearity and small waveguide propagation loss
coefficient.
Keywords- Conjugated polymers, Chain Orientation,
Third-order susceptibility, Waveguide propagation loss
losses, high photostability and easy fabrication of slab
waveguides [1].
Conjugated polymers that posses a delocalized π-electron
system have been considered to be the most promising organic
material candidates for all-optical switching applications
because of their high cubic nonlinearity and fast response
times in the order of picoseconds or less, and relative ease of
waveguide preparation [2]. In particular, poly(pphenylenevinylene) (PPV) was identified as a promising
material for nonlinear optical applications because of large
cubic nonlinearities with fast response times and high damage
thresholds [3]. Recently, its derivatives have incurred much
more interest due to their good combination of large thirdorder nonlinearity and superior waveguide properties [3,4].
Moreover, they are also attractive for electroluminescence
devices [5], plastic laser [6] and transistor [7].
In this paper, we present comparative studies of the linear
and nonlinear optical properties as well as waveguide
properties of newly synthesized of several solution processable
PPV by means of reflectrometry, prism coupling, third
harmonic generation spectroscopy and waveguide propagation
loss. The aim is to study their suitability for application in a
nonlinear all-optical switching planar waveguides. It will be
shown that the conjugated polymer MEH-PPV is the best
suited material for all-optical switching applications due to its
good combination of large value of cubic nonlinearity and
ultimately low waveguide propagation losses.
I. INTRODUCTION
T
he control and processing of fast optical signals is of
increasing importance in integrated optics. Various
concepts for integrated devices based on materials with
high third-order nonlinearities and fast response times
have been suggested [1]. The demonstration of all-optical
switching in planar waveguides would become the
breakthrough in integrated nonlinear optics. The
bottleneck for the realization of such devices is still the
problem of identifying the material that have
multifunctional properties like high third-order
nonlinearity with fast response times, low absorption
II. MATERIALS AND EXPERIMENTAL METHODS
2.1. Materials
The chemical structures of three PPV derivatives: Poly[2methoxy-5-(2-ethylhexyloxy)-1,4-phenylene-vinylene] (MEHPPV); Poly[2,5-dimethoxy-1,4-phenylene-1,2-ethenylene, 2methoxy-5-(2-ethylhexyloxy)-1,4-phenylene-vinylene]
(M3EH-PPV) and their copolymer Poly[2-methoxy-5-(2ethylhexyloxy)-1,4-phenylene-vinylene-2,5-dimethoxy-1,4phenylene-vinylene-2-methoxy-5-(2-ethylhexyloxy)-1,4phenylene-vinylene] (MEH-M3EH-PPV) are displayed in
Figure 1.
117
Proc. of the 2nd International Conf. on Optics and Laser Applications
ICOLA’07, September 5-7, Yogyakarta, Indonesia
O
OCH3
O
CH
CH=CH
CH 3 O
CH3O
MEH-PPV
O
M3EH-PPV
OCH3
O
CH
CH
CH
CH
CH
O
CH
CH3O
CH3O
CH
0.5n
0.5n
CH3O
CH
n
CH3O
CH
CH
CH
n
CH3O
MEH-M3EH-PPV
Figure 1. Chemical structure of MEH-PPV, MEH-M3EH-PPV
and M3EH-PPV
They were synthesized via the polycondensation
route by the use of the Horner-carbonylolefination that
yields well-defined conjugated polymers with excellent
solubility in organic solvents. The weight-average
molecular weight (Mw) and number-average molecular
weight (Mn) of all PPVs were determined with gel
permeation chromatography (GPC) using polystyrene
standards and tetrahydofuran (THF) as eluent. Their
values are displayed in Table 1.
Table 1. Properties of MEH-PPV, MEH-M3EH-PPV and
M3EH-PPV
Polymer
λmax
Two common organic solvents like toluene and
chlorobenzene were used to dissolve the polymers. The
polymers MEH-PPV and MEH-M3EH-PPV were dissolved in
toluene. The polymer M3EH-PPV, however, was dissolved in
chlorobenzene and the solution was heated at approximately
1000C while stirred for 1 hour in order to obtain complete
solubility. Thin films of MEH-PPV and MEH-M3EH-PPV
were prepared by spin coating from freshly prepared and
filtered (0.5 or 1 µm syringe filters) solutions at ambient
atmosphere under a laminar flow. Whereas, thin films of
M3EH-PPV were spin coated at high temperature (~ 1000C).
We varied the concentration by weight (1 - 5 %) and spinning
speed (500 – 9000 rpm) to control the film thickness. The
films were placed subsequently in a vacuum oven at elevated
temperatures (T ≈ 50 0C) for about 6 hours. The thickness d
and the average surface roughness of the films were measured
with a Tencor Model P10 profilometer.
2.2. Linear Optical Constants
Transmission and reflection spectra of thin films (d ≈ 50
nm)
were
measured
by using
a
UV-Vis-NIR
spectrophotometer with electrical field vector oriented parallel
to the film plane (TE-polarization). The dispersions of the
intrinsic absorption coefficient α(λ) and the refractive index
n(λ) of thin films were evaluated from the transmission and
reflection spectra. The absorption spectra and the dispersions
of linear refractive index of thin films of the conjugated
polymers are displayed in Figure 2. Their maxima of
absorption αmax and the maximum wavelengths λmax are shown
in Table 1. The data of λmax have an estimated uncertainty of ±
2 nm because of broad absorption bands.
αmax
Mw
[kg/mol]
Mn
[kg/mol]
[nm]
[104 cm-1]
40.3
14.1
489
12.3
25
20
485
16.1
-1
11.4
15
44.0
12.0
486
18.8
M3EH-PPV
MEH-M3EH-PPV
MEH-PPV
4
32.3
α [10 cm ]
MEHPPV
MEHM3EHPPV
M3EHPPV
10
5
0
(3)
χ max
αgw (TE0)
αgw (TM0)
[dB/cm]
[dB/cm]
Polymer
[10-11 esu]
MEH-PPV
6.50 ± 0.7
0.5 ± 0.3
0.5 ± 0.3
MEHM3EH-PPV
9.65 ± 1.0
12.4 ± 1.4
5.3 ± 1.0
M3EH-PPV
13.8 ± 1.4
> 20
9.4 ± 1.5
118
200
300
400
500
600
λ [nm]
Figure 2. Spectra of the absorption coefficient after correction of
reflection losses of thin films of PPV derivatives at transverse electric
(TE) polarization.
In addition to reflection spectroscopy, we used prism
coupling technique to measure the refractive index of slab
waveguides at several wavelengths between 633 nm and 1064
nm. The typical thicknesses of waveguides were in the range
of 400 - 800 nm. The results are displayed in Figure 3 together
Proc. of the 2nd International Conf. on Optics and Laser Applications
ICOLA’07, September 5-7, Yogyakarta, Indonesia
with the results of transmission-reflection measurements.
We have also measured the refractive index at TM
polarization, nTM of several slab waveguides of PPVs.
The results are displayed in Figure 3 with open symbols.
The values of nTM for these polymers are nearly identical.
2,2
guided mode was launched in the waveguide. The scattered
light from the waveguide was imaged by a lens L2 (focal
length = 50 mm) onto a diode array. Attenuation loss
coefficients αgw were determined from the scattered light
intensity as function of distance from the coupling prism. The
detection limit of this method is in the order of αgw ≈ 0.5
dB/cm.
Closed symbol : TE (prism coupler)
Open symbol : TM (prism coupler)
Lines
: TE (reflectrometry)
PC
Si-Diode array
2,0
M3EH-PPV
MEH-M3EH-PPV
n
MEH-PPV
1,8
L2
Cw Nd:YAG
λ = 1064 nm
A
L1
S
1,6
P
600
700
800
900
1000
1100
Wavelength [nm]
Film
Substrate
Figure 3. Dispersions of refractive indices of MEH-PPV,
MEH-M3EH-PPV and M3EH-PPV.
Figure 4. Setup for waveguide propagation loss measurement.
2.3. Third Harmonic Generation Spectroscopy
Third-harmonic generation (THG) of thin films of
MEH-PPV was measured with a similar setup as
described earlier [3]. We have used a Nd:YAG laser, the
second harmonic output of which pumped an optical
parametric generator, which gave laser pulses with a
duration of 20 ps, repetition rate 10 Hz, and a wavelength
tuning range between 680 nm and 2000 nm. The laser
beam was focused on the sample, which was placed in an
evacuated chamber and mounted on a rotation stage. The
Maker fringes were evaluated taking into account the
measured data of the sample (thickness, refractive index,
and absorption coefficients at the fundamental and
harmonic wavelengths), the free and bound harmonic
waves and their reflections at the interfaces as described
earlier [3]. The only fitting parameters were modulus
⎪χ(3)⎪ and phase angle ϕ of the complex value of χ(3) :
χ(3) = |χ(3)| exp(iϕ). The values of the modulus of ⎪χ(3)⎪
at TE polarization were determined with respect to the
reference value 3.11 10-14 esu for the fused silica
substrate for all laser wavelengths [3].
III. RESULTS AND DISCUSSIONS
2.4. Waveguide Loss Propagation
Waveguide loss experiments were performed by the
prism coupling technique as shown in Figure 4. A cwNd:YAG (1064 nm) laser was used as light source. The
laser beams were coupled into waveguide using a high
refractive index glass prism LaSF18. The film was
clamped onto the half-cut prism mounted on a precision
rotation table. The lens L1 with focal length of 30 cm
was used to focus the laser beam at the coupling edge of
the prism. The coupling angle was adjusted until the
Thin film of M3EH-PPV has the strongest absorption
maximum αmax. It can be understood from the chemical
structures that M3EH-PPV has long alkyl substituents at only
every second phenyl-ring, whereas MEH-PPV contains alkylchains at every phenyl-ring. Meanwhile, the copolymer MEHM3EH-PPV has three alkyl-chains in every four phenyl-rings.
Thus, the reduced amount of alkyl-chains leads to an increase
of the number π-electrons per unit volume and consequently
αmax increases. The dispersions of nTE of these polymers are
shown with solid lines in Figure 3. Similar to the intrinsic
absorption coefficient, nTE increases in the sequence from thin
films of MEH-PPV, MEH-M3EH-PPV to M3EH-PPV. The
dispersions of nTE and nTM of all polymers are shown with
symbols in Figure 3. The results of prism coupling and
reflectometry agree very well which indicates that nTE is not
depending significantly on the film thickness, at least for d =
70 nm and 800 nm. Again, we observe a very pronounced
increase of nTE in the sequence from MEH-PPV, MEH-M3EHPPV to M3EH-PPV. However, we observe nearly identical
values of nTM for all polymers.
In order to study the effect of polymer chain orientation,
we plot the ratio of refractive indices in TE-polarization (inplane) and TM-polarization (out-of-plane) for all polymers
studied in Figure 5. Clearly, the ratio of nTE/nTM is increased in
going from MEH-PPV to MEH-M3EH-PPV and finally to
M3EH-PPV in all spectra region. Since, αmax and refractive
index are correlated to each other; both quantities can show
significant anisotropy in thin films. The electronic π-π*
transition at λmax and the electric polarizability which is related
119
Proc. of the 2nd International Conf. on Optics and Laser Applications
ICOLA’07, September 5-7, Yogyakarta, Indonesia
the chain segments with longer conjugation exhibit much
larger molecular hyperpolarizabilities than those with shorter
conjugation. As a result, the relative contribution of the long
chain segments dominates in the THG process as compared to
the linear absorption. This dominance leads to a red shift of
the |χ(3)| spectra.
8
20
2
0
4
0
300
500
600
MEH-M3EH-PPV
2
0
0
1,05
300
400
500
600
25
4
Figure 5. Ratio of nTE and nTM of MEH-PPV, MEH-M3EHPPV and M3EH-PPV films.
10
5
5
0
300
The dispersions of the modulus of χ(3) at 1/3 of the
fundamental wavelength compared with linear absorption
spectra for all PPVs studied are displayed in Figure 6.
The χ(3) values exhibit a strong spectral dependence on
the laser wavelength λL because of three-photon
resonances with electronic states of the polymers. The
spectrum of the χ(3) resembles the linear absorption
coefficient: it has a maximum, denoted χ(3)max, at the
laser wavelength λL ≈ 3λmax of the absorption coefficient.
The strong maximum of χ(3)max is ascribed to a threephoton resonance with states located at the top of the
valence band and the exciton state. It occurs at
wavelength λL(χ(3)max) ≈ 3λmax of linear absorption
coefficient. The values of χ(3)max of all PPVs studied are
given in Table 1.
The peaks of χ(3) spectra of all-PPVs are red shifted
as compared to their λmax. These shifts are explained as a
consequence of the statistical distribution on the effective
π-conjugation length. As the second order molecular
hyperpolarizability, which is responsible for the process
of THG increases strongly with the conjugation length,
10
15
esu]
1100
-11
1000
[10
900
χ
800
Wavelength [nm]
-1
700
20
α [10 cm ]
600
120
15
M3EH-PPV
1,00
-11
(3)
4
5
χ
1,10
6
10
[10
8
15
esu]
-1
10
(3)
1,15
20
400
4
MEH-PPV
MEH-M3EH-PPV
M3EH-PPV
α [10 cm ]
Ratio of nTE/nTM
1,20
-11
5
[10
4
(3)
10
χ
6
-1
15
esu]
MEH-PPV
α [10 cm ]
to n, are both highly polarized and have their main
components in the chain direction of PPV. Consequently,
αmax and n are largest if the electric field of incident light
is parallel to the chain direction. If the PPV chains
become increasingly aligned parallel to the substrate
plane, it is evident that αmax which is measured at E
parallel to the film plane, and nTE will increase. This
behavior strongly indicates that amount of PPV chain
segments aligned parallel to the substrate plane in thin
film is increased in going from MEH-PPV, MEH-M3EHPPV and finally to M3EH-PPV. Recently, we observed
this effect in thin films of MEH-PPV, which were
prepared from different molecular weight, Mw. The chain
segments show an increased tendency to align parallel to
the layer plane with increasing Mw [8].
0
400
500
600
λ, λL/3 [nm]
Figure 6. Spectra of the modulus of χ(3) at λL/3 in comparison with
linear absorption spectra of thin films of MEH-PPV, MEH-M3EHPPV and M3EH-PPV.
As can be seen in Table 1, the χ(3) values is increased in
going from MEH-PPV, MEH-M3EH-PPV and M3EH-PPV
which might be indicated that a more ordered and planar
arrangement of the polymer chains was promoted in spin cast
film M3EH-PPV as discussed above. A planar arrangement of
the polymer chains is expected to enhance the nonlinear
optical response in force of the reduced dimensionality of the
π-electron delocalisation. This hypothesis of in-plane ordering
was also supported by the anisotropy as displayed in Figure 5.
Thin film prepared from M3EH-PPV showed the larger
refractive index and birefringence that that of MEH-PPV and
its copolymer, what is an indication of an increased ordering.
Our recent study shows that the third order susceptibility χ(3)
of thin films of MEH-PPV is increased with the orientation of
polymer chains parallel to the substrate [9]. The density of
polymer might be another factor that influence the χ(3) value.
Proc. of the 2nd International Conf. on Optics and Laser Applications
ICOLA’07, September 5-7, Yogyakarta, Indonesia
The waveguide propagation loss was determined by
measuring the stray light of TE modes as a function of
distance from the coupling prism. Figure 7 shows the
stray light at the diode array for MEH-PPV and MEHM3EH-PPV slab waveguides.
TE0 at 1064 nm
Intensity [a.u.]
10
3
MEH-PPV
MEH-M3EH-PPV
10
2
0,0
0,5
1,0
1,5
2,0
x [cm]
Figure 7. Intensity of the light scattered from TE0 modes of
waveguides of MEH-PPV and MEH-M3EH-PPV versus
distance from the prism at λ = 1064 nm.
IV. CONCLUSIONS
We have performed comparative studies of three polymer
films of PPV derivatives by means of reflectrometry, prism
coupler, third harmonic generation spectroscopy and
waveguide propagation loss. We have shown that the length of
alkyl side chains affects both the linear and nonlinear optical
properties as well as waveguide properties. The reduced
amount of alkyl-chains leads to an increase of the number πelectrons per unit volume, therefore, more polymer chain
segments are oriented parallel to the layer plane. As
consequences, the αmax, nTE , and χ(3) increase in the sequence
from MEH-PPV, MEH-M3EH-PPV to M3EH-PPV. However,
the reduced of alkyl-chains substitution reduce of solubility
which leads to the gel formation. Therefore, both αgw (TE0)
and αgw (TM0) are increased. We have concluded that thin
films of the conjugated polymers MEH-PPV is the most
appropriate candidate for all-optical switching applications,
because it exhibit good combination of large value of cubic
nonlinearity and ultimately low waveguide propagation loss
coefficient.
REFERENCES
The slopes of the lines fitted to the experimental data
yield the loss coefficients of the guided waves αgw. The
values of αgw of all PPVs both in TE- and TMpolarizations are presented in Table 1. They contain the
contributions of intrinsic absorption and the scattering
losses, which depend on the surface roughness of the
waveguide. Although the values of the relative surface
roughness (Ra/d) of all PPVs are comparable (0.5 –
1.2 %), they exhibit different values of αgw. This might
be related to aggregate formation caused by a different
solubility of the polymers. The substitution with the
branched 2-ethylhexyloxy group causes very good
solubility of the PPVs. We observed that the solubility is
reduced in going from MEH-PPV to MEH-M3EH-PPV
and finally to M3EH-PPV due to the decrease of the
relative number of this “solubility providing” substituent
(Figure 1). Consequently, an increased tendency of
aggregate formation is imaginable which would cause an
increase of light scattering in the sequence of these three
PPVs. As a consequence, αgw in both TE and TM
polarizations increases. Another factor might be related
to the different morphology of the films. Our recent study
of thin films MEH-PPV shows that the large changes of
αgw can be caused by different morphology of thin films,
in particular on the arrangement of polymer chains in the
films [8].
[1]. G. I. Stegeman, “Material figures of merit and implications to
all-optical waveguide switching”, Proc. SPIE Vol. 1852, pp. 7589, 1993.
[2]. F. Kajzar, and J.D. Swalen, Eds.; Organic Thin Films for
Waveguiding Nonlinear Optics; Gordon and Breach Publ.:
Amsterdam, 1996.
[3]. A. Mathy, K. Ueberhofen, R. Schenk, H. Gregorius, R. Garay, K.
Müllen, and C. Bubeck, “Third-harmonic-generation
spectroscopy of poly(p-phenylenevinylene): A comparison with
oligomers and scaling laws for conjugated polymers”, Phys. Rev.
B Vol. 53, pp. 4367-4376, 1996.
[4]. M.A. Bader, G. Marowsky, A. Bahtiar, K. Koynov, C. Bubeck,
H. Tillmann, H.-H. Hörhold, and S. Pereira, “Poly(pphenylenevinylene) derivatives: new promising materials for
nonlinear all-optical waveguide switching”, J. Opt. Soc. Am. B
Vol. 19, pp. 2250-2262, 2002.
[5]. R.H. Friend, R.W. Gymer, A.B. Holmes, J.H. Burroughes, R.N.
Marks, C. Taliani, D.D.C. Bradley, D.A. Dos Santos, J.L.
Bredas, M. Logdlund, and W.R. Salaneck, “Electroluminescence
in conjugated polymers”, Nature Vol. 397, pp. 121-128, 1999.
[6]. M.D. McGehee, and A.J. Heeger, “Semiconducting (conjugated)
polymers as materials for solid-state lasers”, Adv. Mater. Vol.
12, pp. 1655-1668, 2000.
[7]. J. Zaumseil, R.H. Friend, and H. Sirringhaus, “Spatial control of
the recombination zone in an ambipolar light-emitting organic
transistor”, Nature. Mater. Vol. 5, pp. 69-74, 2006.
[8]. K. Koynov, A. Bahtiar, T. Ahn, R.M. Cordeiro, H.-H. Hörhold,
and C. Bubeck, “Molecular weight dependence of chain
orientation and optical constants of thin films of the conjugated
polymer MEH-PPV”, Macromolecules Vol. 39, pp. 8692-8698,
2006.
[9]. A. Bahtiar, K. Koynov, T. Ahn, and C Bubeck,” The effect of
molecular weight on the third-order nonlinear optical
susceptibility in thin MEH-PPV films” 2006, submitted.
121
P R OC E E D I N G
THE 2nndd
INTERNATIONAL CONFERENCE ON
OPTICS AND LASER APPLICATIONS
ICOLA’07
Yogyakarta, INDONESIA
September 5-7, 2007
Organized by:
The Study Program on
Opto-Electrotechniques and Laser Applications
Dept. of Electrical Engineering, University of Indonesia
Indonesia Section
ISBN Number: 978-979-8575-05-1
PROCEEDING
THE 2nndd
INTERNATIONAL CONFERENCE ON
OPTICS AND LASER APPLICATIONS
ICOLA’07
Yogyakarta, INDONESIA
September 5-7, 2007
Indonesia Section
Organized by:
The Study Program on
Opto-Electrotechniques and Laser Applications
Dept. of Electrical Engineering, University of Indonesia
i
© PS-OEAL
The Study Program on Opto-Electrotechniques and Laser Applications
Dept. of Electrical Engineering, University of Indonesia
All right reserved. No part of this publication may be reproduced, stored in a
retrieval system, or transmitted in any form or by any means, electronics,
mechanical, photocopying, recording or otherwise, without the prior permission ot
the copyright owner.
PS-OEAL, Dept of Electrical Engineering, University of Indonesia
Jl. Salemba Raya 4, Jakarta Pusat 10430, Indonesia
Phone (62) 21 330188, Fax. (62) 21 391115, Email: spsopto@bit.net.id
http://opto.eng.ui.ac.id
ii
Preface
Dear the ICOLA 2007 Participants
On behalf of the Committee of International Conference on Optics and Laser Applications, ICOLA’07
allow me to express my gratitude to all of you, who participate in this conference. The Study Program on
Opto-Electrotechniques and Laser Applications, Dept. Electrical Engineering, University of Indonesia
organizes this conference in conjunction with the 30th anniversary of the study program.
The ICOLA’07 is technically supported by the International Commission for Optics (ICO), International
Society for Optical Engineering (SPIE), and the Abdul Salam International Center for Theoretical
Physics (ICTP), in cooperation with other professional society like: HFI, HAI, IEEE Indonesia Section,
etc. We would like to warmly welcome the participants from USA, Japan, South Korea, P.R. China,
Taiwan, Thailand, Singapore, Malaysia, Bangladesh, India, Iran, Yemen, Algiers, Moldova, Ukraine, the
Netherlands, etc., especially the distinguished professors from the well known and recognized
institutions as invited speakers.
The time of conference is remarked by a significant progress in science and technology, especially in
the field opto-electronics and laser applications. Although our country is facing with political and
economical problems, in fact, there are still some researchers, young engineers, students --who are
working in their own fields-- wishing to present their works in this conference.
We received around 81 extended abstracts (invited, overseas, and domestic) but only about 55 selected
or reviewed papers will be presented in the conference. These are divided into three categories:
A: Nanotechnology, Biomedical Optics, and Optical Communication
B: General Optics, Holography, and Laser Technology
C: Photonic Devices/Materials, Design, and Applications
We would like to thank to all Committee members, to all organizations and sponsors who have provided
their supports and efforts to make this conference become a success. In addition, thanks also are
forwarded to all individuals for their valuable time and supports to the conference.
Finally, have intensive discussions in the conference and enjoyable stay in Yogyakarta !
Prof. Dr. Sar Sardy
General Chairman of ICOLA2007
iii
ICOLA2007 Committee Members
Organizer
The Study Program on Opto-electrotechnique and Laser Applications (OEAL)
Department of Electrical Engineering, Faculty of Engineering, University of Indonesia
Sponsor (technical)
ICO, SPIE, ICTP, IEEE Indonesia Section, Indonesian Physical Society, Indonesian Astronomical Society
International Program Committee
Prof. Dr. Suganda Jutamulia, Chair, Univ. of Nothern California, USA
Prof. Dr. Yashuhiru Suematsu, The Past President Tokyo Institute of Technology
Prof. Dr. Jumpei Tsujiuchi, Prof. Emeritus Tokyo Institute of Technology
Prof. Dr. Toshimitsu Asakura, Prof. Emeritus Hokkaido University
Prof. Dr. Guoguang Mu, Nankai University, China
Prof. Dr. Lambertus Hesselink, Stanford Univ. USA
Prof. Dr. Mohammad S. Alam, Univ. of South Alabama, USA
Prof. Dr. Francis Yu, Pennsylvania State University, USA
Prof. Dr. Cardinal Warde, Massachusetts Inst. Tech. USA
Prof. Dr. Pochi Yeh, Univ. of California Santa Barbara, USA
Prof. Dr. Alexander Sawchuck, SIPI, Univ. of Southern California, USA
Prof. Dr. Kehar Singh, Indian Inst. Tech. Delhi, India
Prof. Dr. Rene Dandliker, President SATW, Switzerland
Prof. Dr. Gallieno Denardo, ICTP, Trieste, Italy
Prof. Dr. Min Gu, Swinburne Univ. of Technology, Australia
Prof. Dr. Arthur Chiou, National Yang Ming Univ., Taiwan
Prof. Dr. Joewono Widjaja, Suranaree Univ. of Technology, Thailand
Prof. Dr. Anand Krishna Asundi, Nanyang Technological Univ. Singapore
Prof. Dr. Yoshizumi Yasuda, Tokyo University for Information Science, Japan
Prof. Dr. Yoshihisa Aizu, Muroran Inst. Tech. Japan
Prof. Dr. Byoung Yoon Kim, Novera Optics, KT Second Research Center, South Korea
Prof. Dr. Feijun Song, China Daiheng Coorp., P.R. China
Prof. Dr. Kazuhiko Ohnuma , Chiba University, Japan
Prof. Dr. A.N. Chumakov, National Academy of Science, Belarus
Dr. Yoshiji Suzuki, Hamamatsu Photonics KK, Japan
Advisory Committee
Prof. Dr. Rinaldy Dalimi, Chair, Dean Fac. of Engineering, University of Indonesia
Prof. Dr. Eko Tjipto Rahardjo, University of Indonesia
Prof. Dr. Bambang Hidayat, Chairman Indonesian Academy of Science
Prof. Dr. Zuhal, President Indonesian Al-Azhar University
Prof. Dr. Budi Santoso, Indonesian Atomic Energy Agency
Prof. Dr. Tjia May On, Bandung Institute of Technology
General Chairman
Sar Sardy, Professor, Head of OEAL-FTUI, Univ. of Indonesia
Technical Program Committee
Dr. Gunawan Witjaksono, Chair, University of Indonesia
Prof. Dr. Dadang Gunawan, IEEE-Indonesia Section
iv
Prof. Dr. Anung Kusnowo, Indonesian Institute of Science
Dr. Ary Syahriar, Indonesian Al-Azhar University
Dr. Henri Putra Uranus, University of Twente, the Netherlands
Dr. Ir. Sekartedjo, Sepuluh Nopember Institute of Technology
Dr. Hendrik Kurniawan, University of Indonesia
Prof. Dr. Masbach R. Siregar, Indonesian Physical Society
Dr. Hakim L. Malasan, Indonesian Astronomical Society
Local Organizing Committe
Dr. Ir. Purnomo Sidi Priambodo, MSEE, Chair, University of Indonesia
Dr. Ir. Dodi Sudiana, MEng, University of Indonesia
Dr. Ir. Retno Wigajatri MEng, University of Indonesia
Dr. Abdul Muis, ST. MEng, University of Indonesia
Dr. Ir. Feri Yusivar, MEng, University of Indonesia
Fitri Yuli Zulkifli, ST. MSc, University of Indonesia
Arief Udhiarto, ST. MT, University of Indonesia
Budi Sudiarto, ST. MT, University of Indonesia
Muhammad Suryanegara, ST. MSc, University of Indonesia
F. Ashta Ekadiyanto, ST. MSc, University of Indonesia
Aji Nur Widyanto, ST, University of Indonesia
v
CONTENT
Invited-Planery Papers
Scientists and Their Society: Between Advocacy and Arbitration
1
Bambang Hidayat
Angular Division Multiplexing in Pulsed Digital Holography for
Recordings of High Resolution
7
Hongchen Zhai, Xiaolei Wang, CaojinYuan and Guoguang Mu
Design and analysis for laser beaming devices using surface plasmon
resonance
12
Byoungho Lee, Hwi Kim, and Seyoon Kim
Phase Singularity Distribution of Fractal Speckles
17
Jun Uozumi
Laser Aided Golf Trainer – Product and Business Development
22
Suganda Jutamulia
Quality of Images Reconstructed from In-Line Fresnel Holograms
25
Joewono Widjaja and Phacharawadee Raweng
Three-dimensional computer-generated holographic display of
biological tissue
30
Toyohiko Yatagai Yusuke Sando , Ken-ichi Miura and Masahide Itoh
,
Application of VIS-NIR Spectral Imaging to Skin Tissue
Measurements
34
Yoshihisa Aizu, Takaaki Maeda, and Izumi Nishidate
On-demand optical tweezers by time-division multiplexing of
computer-generated holograms
39
Toshiaki IWAI and Johtaro YAMAMOTO
Digital holography a new paradigm for imaging, microscopy
and measurement
43
Anand Asundi and Vijay Raj Singh
Encrypted Content-addressable Holographic Memories
Kehar Singh, Renu John, and Joby Joseph
vi
48
Three-Dimensional Microscopic Imaging
53
Colin J.R. Sheppard
Contributed Papers : Overseas
Enhancing the Performance of Integrated Optical Sensor by
Slow-light: Theoretical Study on Ring-Resonator Based Structures
56
Henri P. Uranus, and Hugo J. W. M. Hoekstra
Electro-Optical Studies Of Chemically Deposited Znxcd1-X
Nanocrystalline Films
61
Shashi Bhushan and Ayush Khare
Compact Optical Sensor for Soil Nutrients Analysis by using LEDs
66
Masayuki Yokota
Precision Dynamic Force Measurement Using Mass Levitation and
Optical Interferometer
70
Yusaku FUJII
Optical properties of vanadium doped ZnTe thin cermet films for
selective surface applications
74
M. S. Hossain, R. Islam and K. A. Khan
Improved 90° Bend Transmission Defined in a Triangular Lattice
Photo nic Crystals
79
Leila DEKKICHE, and Rafah NAOUM
Dual Ball Lenses for Relaxed Alignment Tolerances in Pigtailing of a
Laser Diode Transmitter
83
Mohamed Fadhali, Saktioto,Jasman Zainal, Yusof Munajat, Jalil Ali and Rosly Abdul Rahman
Normalized Frequency Gradient of Coupled Fibers as a Function of
Coupling Ratio
88
Saktioto, Jalil Ali, Jasman Zainal, Mohamed Fadhali
Experimental studies on the short wave transmission characteristics of
a laser protection filter coating used in the laser optical systems
93
Nimmagadda Rama Murthy, and A.S. Murthy
Two-Photon Lasing Controlled by Resonator Losses
98
Vitalie Eremeev, Marina Turcan, Nicolae Enaki
Incoherent Light Depolarization by Multiple Reflections
Yaroslav Aulin
vii
103
Influence of Filters on Recognition of Noisy Objects
107
Seyed Mohsen Mirsadri, Hosein Bolandi, Farhad Fani Saberi
Design and Development of Holographic Sighting System used for
small arm weapons in Close Quarter Battle situations
113
Nimmagadda Rama Murthy, P.Rajesh Kumar, and N. Raghavender
Contributed Papers : Domestic
The Effects of Substitution on the Optical Properties of
poly(p-phenylenevinylene) Derivatives
117
A. Bahtiar and C. Bubeck
Possible use of formaldehyde as fluorescence tracer to examine the
state of mixture formation in Spark Ignited (SI) engines
122
A.M.T Nasution1, V. Beushausen, R. Mueller
The Parameter Modeling of Grating Reflector for External Cavity
Tunable Lasers as light sources in DWDM System
127
Supriyanto
Surface Roughness Measurement by Electronics Speckle Pattern
Interferometry (ESPI) Method
131
A.S. Pramono, Rakiman, D. Ardiansyah , H. Setijono
Generalized Linear Dispersion Relation for Symmetrical
Directional-coupler of Five-layer Waveguide
135
Sekartedjo, and Ali Yunus Rohedi
Design of Multimode Interference Structure for 1x2 Optical
Waveguide Filter for 1.3 and 1.55 µm
140
Sekartedjo, and Agus Muhamad Hatta
Phase Unwrapping Applied to Digital Holography
143
D. Ardiansyah and Sekartedjo
Introducing Stable Modulation Technique for Solving an
Inhomogeneous Bernoulli Differential Equation
147
Ali Yunus Rohedi
High Temperature Annealing effects on Silica based Optical
Waveguides
Ary Syahriar
viii
152
Simple Model of Design 1.55μm and 1.31μm VCSEL’s for High Speed
Modulation Optical Interconnections
158
Gunawan Witjaksono, Ucuk Darusalam, Gunady Haryanto, Arum Setyowati
Simulation GaInAsP/InP Surface Emitting Distributed Feedback
Laser for Radio Over Fiber Application
163
Gunawan Witjaksono, Irma Saraswati
Optical Waveguide Directional Fiber Coupler Design Method Based
on Numerical Analysis
167
Ucuk Darusalam, Gunady H., Arum Setyowati, Purnomo Sidi Priambodo, V. Vekky R. R
Gain Characteristics Analysis of Distributed Raman Amplifier on
CWDM Band Based on Numerical Simulation
172
V. Vekky R. Repi, Ucuk Darusalam, Purnomo Sidi Priambodo
Design of Multimode Interference (MMI) Couplers Using Method of
Lines
177
Helmi Adam, Ary Syahriar
Design of Three Parallel Waveguide Using Coupled Mode Theory and
Method of Lines
Helmi Adam, Dwi Astharini, Ary Syahriar
181
Laser Micromachining of Silicon and Its Application for the
Fabrication of Micro Gas Sensor Device
185
Goib Wiranto,Gandi Sugandi, I Dewa P. Hermida, and Edy Supriyanto
Edge-element based finite element analysis of leaky modes of photonic
crystal microcavities
189
Ardhasena Sopaheluwakan
Measurement of the nonlinear susceptibility of the third order
dielectric materials by means of Z-scan technique
193
Freddy Susanto Tan
Optical Fibre Biosensor Based on Enzymatically Doped Sol-Gel
Glasses for Monitoring of Pesticides in Flow System
197
Bambang Kuswandi, Chulaifah Indah Fikriyah, Agus Abdul Gani and Anak Agung Istri
Ratnadewi
Simulations of rib waveguide structure with trapezoidal cross-section
using Finite Difference Method
Suwasti Broto, N. Mohd Kassim, M.H. Ibrahim
ix
202
Achieving gain flatness in C-band Erbium Doped Fiber
Amplifiers
207
Sholeh Hadi Pramono, Sar Sardy, Ary Syahriar, Irwan R.Hc, Sasono R
Design and Implementation of Knowledge-Based Expert Systems GIS
for Fishing Ground Prediction Models: a preliminary results
210
Muhamad Sadly, and Yoke Faisal
The Assessment of Fish Abundance by using Modis Satellite Data of
SSC and SST (Case Study : In the South Kalimantan)
214
Suhendar I Sachoemar, Muhamad Sadly and Fanny Meliani
Fitting of Linear Transducer Characteristic using Genetic Algorithm
and Segmented by Golden Ratio
Purwowibowo, Sar Sardy, and Wahidin Wahab
219
Visible to Near Infrared Spectrum
Reflectance Ratios in Cancer Detection
224
Hamdani Zain, Anwar S. Ibrahim, Aryo Tedjo and Kusmardi
Speech Recognition for Controlling Movement of the Wheelchair
227
Thiang
A Comparison of Discrete Cosine Transform and Discrete Wavelet
Transform Techniques in Audio Compression
232
Endra
Face Identification with Multi-resolution Method
235
Indra Riyanto, and Wihartini
Splice Loss: Estimated Value Versus OTDR Measurement
238
Dwi Bayuwati, Tomi Budi Waluyo, Imam Mulyanto
The Spectral Reflectance Characteristic of Coral and Its Relation to
The Optic Properties of Waters
242
Nurjannah Nurdin, Muhamad Sadly, Indra Jaya, Vincentius Siregar
Introducing “OPTO”: Portal for Optical Communities in Indonesia
Tomi Budi Waluyo and Laksana Tri Handoko
x
245
Proc. of the 2nd International Conf. on Optics and Laser Applications
ICOLA’07, September 5-7, Yogyakarta, Indonesia
The Effects of Substitution on the Optical Properties of
poly(p-phenylenevinylene) Derivatives
A. Bahtiar* and C. Bubeck†
*
Department of Physics, University of Padjadjaran Bandung, Jl. Jatinangor km. 21 Sumedang, 45363, Indonesia.
Tel. ++62-22-7796014, Fax. ++62-22-7792435, email: ayibahtiar@yahoo.com
†
Max Planck Institute for Polymer Research, Ackermannweg 10, D-55128 Mainz, Germany
Tel. ++49-6131-379122, Fax. ++49-6131-379100, email: bubeck@mpip-mainz.mpg.de
Abstract - We have studied the optical linear, optical
nonlinear and waveguide properties of thin films of
newly synthesized poly(phenylenevinylene) (PPV)
derivatives: MEH-PPV, M3EH-PPV and copolymer
MEH-M3EH-PPV by means of reflectrometry, prism
coupling, third harmonic generation spectroscopy
and waveguide propagation loss. Anisotropic
refractive index measurements by means of
waveguide prism coupling and reflectometry were
used to analyse the polymer chain orientation in the
films. We observed that the absorption coefficient,
refractive index, birefringence and third order
susceptibility and waveguide loss coefficient are
increased in going from MEH-PPV, MEH-M3EHPPV and finally to M3EH-PPV, which indicates that
the thin film of M3EH-PPV have the most polymer
chain segments oriented parallel to the film plane. For
all-optical switching applications, the thin film of
MEH-PPV is the most appropriate candidate, since it
exhibit a good combination of large value of cubic
nonlinearity and small waveguide propagation loss
coefficient.
Keywords- Conjugated polymers, Chain Orientation,
Third-order susceptibility, Waveguide propagation loss
losses, high photostability and easy fabrication of slab
waveguides [1].
Conjugated polymers that posses a delocalized π-electron
system have been considered to be the most promising organic
material candidates for all-optical switching applications
because of their high cubic nonlinearity and fast response
times in the order of picoseconds or less, and relative ease of
waveguide preparation [2]. In particular, poly(pphenylenevinylene) (PPV) was identified as a promising
material for nonlinear optical applications because of large
cubic nonlinearities with fast response times and high damage
thresholds [3]. Recently, its derivatives have incurred much
more interest due to their good combination of large thirdorder nonlinearity and superior waveguide properties [3,4].
Moreover, they are also attractive for electroluminescence
devices [5], plastic laser [6] and transistor [7].
In this paper, we present comparative studies of the linear
and nonlinear optical properties as well as waveguide
properties of newly synthesized of several solution processable
PPV by means of reflectrometry, prism coupling, third
harmonic generation spectroscopy and waveguide propagation
loss. The aim is to study their suitability for application in a
nonlinear all-optical switching planar waveguides. It will be
shown that the conjugated polymer MEH-PPV is the best
suited material for all-optical switching applications due to its
good combination of large value of cubic nonlinearity and
ultimately low waveguide propagation losses.
I. INTRODUCTION
T
he control and processing of fast optical signals is of
increasing importance in integrated optics. Various
concepts for integrated devices based on materials with
high third-order nonlinearities and fast response times
have been suggested [1]. The demonstration of all-optical
switching in planar waveguides would become the
breakthrough in integrated nonlinear optics. The
bottleneck for the realization of such devices is still the
problem of identifying the material that have
multifunctional properties like high third-order
nonlinearity with fast response times, low absorption
II. MATERIALS AND EXPERIMENTAL METHODS
2.1. Materials
The chemical structures of three PPV derivatives: Poly[2methoxy-5-(2-ethylhexyloxy)-1,4-phenylene-vinylene] (MEHPPV); Poly[2,5-dimethoxy-1,4-phenylene-1,2-ethenylene, 2methoxy-5-(2-ethylhexyloxy)-1,4-phenylene-vinylene]
(M3EH-PPV) and their copolymer Poly[2-methoxy-5-(2ethylhexyloxy)-1,4-phenylene-vinylene-2,5-dimethoxy-1,4phenylene-vinylene-2-methoxy-5-(2-ethylhexyloxy)-1,4phenylene-vinylene] (MEH-M3EH-PPV) are displayed in
Figure 1.
117
Proc. of the 2nd International Conf. on Optics and Laser Applications
ICOLA’07, September 5-7, Yogyakarta, Indonesia
O
OCH3
O
CH
CH=CH
CH 3 O
CH3O
MEH-PPV
O
M3EH-PPV
OCH3
O
CH
CH
CH
CH
CH
O
CH
CH3O
CH3O
CH
0.5n
0.5n
CH3O
CH
n
CH3O
CH
CH
CH
n
CH3O
MEH-M3EH-PPV
Figure 1. Chemical structure of MEH-PPV, MEH-M3EH-PPV
and M3EH-PPV
They were synthesized via the polycondensation
route by the use of the Horner-carbonylolefination that
yields well-defined conjugated polymers with excellent
solubility in organic solvents. The weight-average
molecular weight (Mw) and number-average molecular
weight (Mn) of all PPVs were determined with gel
permeation chromatography (GPC) using polystyrene
standards and tetrahydofuran (THF) as eluent. Their
values are displayed in Table 1.
Table 1. Properties of MEH-PPV, MEH-M3EH-PPV and
M3EH-PPV
Polymer
λmax
Two common organic solvents like toluene and
chlorobenzene were used to dissolve the polymers. The
polymers MEH-PPV and MEH-M3EH-PPV were dissolved in
toluene. The polymer M3EH-PPV, however, was dissolved in
chlorobenzene and the solution was heated at approximately
1000C while stirred for 1 hour in order to obtain complete
solubility. Thin films of MEH-PPV and MEH-M3EH-PPV
were prepared by spin coating from freshly prepared and
filtered (0.5 or 1 µm syringe filters) solutions at ambient
atmosphere under a laminar flow. Whereas, thin films of
M3EH-PPV were spin coated at high temperature (~ 1000C).
We varied the concentration by weight (1 - 5 %) and spinning
speed (500 – 9000 rpm) to control the film thickness. The
films were placed subsequently in a vacuum oven at elevated
temperatures (T ≈ 50 0C) for about 6 hours. The thickness d
and the average surface roughness of the films were measured
with a Tencor Model P10 profilometer.
2.2. Linear Optical Constants
Transmission and reflection spectra of thin films (d ≈ 50
nm)
were
measured
by using
a
UV-Vis-NIR
spectrophotometer with electrical field vector oriented parallel
to the film plane (TE-polarization). The dispersions of the
intrinsic absorption coefficient α(λ) and the refractive index
n(λ) of thin films were evaluated from the transmission and
reflection spectra. The absorption spectra and the dispersions
of linear refractive index of thin films of the conjugated
polymers are displayed in Figure 2. Their maxima of
absorption αmax and the maximum wavelengths λmax are shown
in Table 1. The data of λmax have an estimated uncertainty of ±
2 nm because of broad absorption bands.
αmax
Mw
[kg/mol]
Mn
[kg/mol]
[nm]
[104 cm-1]
40.3
14.1
489
12.3
25
20
485
16.1
-1
11.4
15
44.0
12.0
486
18.8
M3EH-PPV
MEH-M3EH-PPV
MEH-PPV
4
32.3
α [10 cm ]
MEHPPV
MEHM3EHPPV
M3EHPPV
10
5
0
(3)
χ max
αgw (TE0)
αgw (TM0)
[dB/cm]
[dB/cm]
Polymer
[10-11 esu]
MEH-PPV
6.50 ± 0.7
0.5 ± 0.3
0.5 ± 0.3
MEHM3EH-PPV
9.65 ± 1.0
12.4 ± 1.4
5.3 ± 1.0
M3EH-PPV
13.8 ± 1.4
> 20
9.4 ± 1.5
118
200
300
400
500
600
λ [nm]
Figure 2. Spectra of the absorption coefficient after correction of
reflection losses of thin films of PPV derivatives at transverse electric
(TE) polarization.
In addition to reflection spectroscopy, we used prism
coupling technique to measure the refractive index of slab
waveguides at several wavelengths between 633 nm and 1064
nm. The typical thicknesses of waveguides were in the range
of 400 - 800 nm. The results are displayed in Figure 3 together
Proc. of the 2nd International Conf. on Optics and Laser Applications
ICOLA’07, September 5-7, Yogyakarta, Indonesia
with the results of transmission-reflection measurements.
We have also measured the refractive index at TM
polarization, nTM of several slab waveguides of PPVs.
The results are displayed in Figure 3 with open symbols.
The values of nTM for these polymers are nearly identical.
2,2
guided mode was launched in the waveguide. The scattered
light from the waveguide was imaged by a lens L2 (focal
length = 50 mm) onto a diode array. Attenuation loss
coefficients αgw were determined from the scattered light
intensity as function of distance from the coupling prism. The
detection limit of this method is in the order of αgw ≈ 0.5
dB/cm.
Closed symbol : TE (prism coupler)
Open symbol : TM (prism coupler)
Lines
: TE (reflectrometry)
PC
Si-Diode array
2,0
M3EH-PPV
MEH-M3EH-PPV
n
MEH-PPV
1,8
L2
Cw Nd:YAG
λ = 1064 nm
A
L1
S
1,6
P
600
700
800
900
1000
1100
Wavelength [nm]
Film
Substrate
Figure 3. Dispersions of refractive indices of MEH-PPV,
MEH-M3EH-PPV and M3EH-PPV.
Figure 4. Setup for waveguide propagation loss measurement.
2.3. Third Harmonic Generation Spectroscopy
Third-harmonic generation (THG) of thin films of
MEH-PPV was measured with a similar setup as
described earlier [3]. We have used a Nd:YAG laser, the
second harmonic output of which pumped an optical
parametric generator, which gave laser pulses with a
duration of 20 ps, repetition rate 10 Hz, and a wavelength
tuning range between 680 nm and 2000 nm. The laser
beam was focused on the sample, which was placed in an
evacuated chamber and mounted on a rotation stage. The
Maker fringes were evaluated taking into account the
measured data of the sample (thickness, refractive index,
and absorption coefficients at the fundamental and
harmonic wavelengths), the free and bound harmonic
waves and their reflections at the interfaces as described
earlier [3]. The only fitting parameters were modulus
⎪χ(3)⎪ and phase angle ϕ of the complex value of χ(3) :
χ(3) = |χ(3)| exp(iϕ). The values of the modulus of ⎪χ(3)⎪
at TE polarization were determined with respect to the
reference value 3.11 10-14 esu for the fused silica
substrate for all laser wavelengths [3].
III. RESULTS AND DISCUSSIONS
2.4. Waveguide Loss Propagation
Waveguide loss experiments were performed by the
prism coupling technique as shown in Figure 4. A cwNd:YAG (1064 nm) laser was used as light source. The
laser beams were coupled into waveguide using a high
refractive index glass prism LaSF18. The film was
clamped onto the half-cut prism mounted on a precision
rotation table. The lens L1 with focal length of 30 cm
was used to focus the laser beam at the coupling edge of
the prism. The coupling angle was adjusted until the
Thin film of M3EH-PPV has the strongest absorption
maximum αmax. It can be understood from the chemical
structures that M3EH-PPV has long alkyl substituents at only
every second phenyl-ring, whereas MEH-PPV contains alkylchains at every phenyl-ring. Meanwhile, the copolymer MEHM3EH-PPV has three alkyl-chains in every four phenyl-rings.
Thus, the reduced amount of alkyl-chains leads to an increase
of the number π-electrons per unit volume and consequently
αmax increases. The dispersions of nTE of these polymers are
shown with solid lines in Figure 3. Similar to the intrinsic
absorption coefficient, nTE increases in the sequence from thin
films of MEH-PPV, MEH-M3EH-PPV to M3EH-PPV. The
dispersions of nTE and nTM of all polymers are shown with
symbols in Figure 3. The results of prism coupling and
reflectometry agree very well which indicates that nTE is not
depending significantly on the film thickness, at least for d =
70 nm and 800 nm. Again, we observe a very pronounced
increase of nTE in the sequence from MEH-PPV, MEH-M3EHPPV to M3EH-PPV. However, we observe nearly identical
values of nTM for all polymers.
In order to study the effect of polymer chain orientation,
we plot the ratio of refractive indices in TE-polarization (inplane) and TM-polarization (out-of-plane) for all polymers
studied in Figure 5. Clearly, the ratio of nTE/nTM is increased in
going from MEH-PPV to MEH-M3EH-PPV and finally to
M3EH-PPV in all spectra region. Since, αmax and refractive
index are correlated to each other; both quantities can show
significant anisotropy in thin films. The electronic π-π*
transition at λmax and the electric polarizability which is related
119
Proc. of the 2nd International Conf. on Optics and Laser Applications
ICOLA’07, September 5-7, Yogyakarta, Indonesia
the chain segments with longer conjugation exhibit much
larger molecular hyperpolarizabilities than those with shorter
conjugation. As a result, the relative contribution of the long
chain segments dominates in the THG process as compared to
the linear absorption. This dominance leads to a red shift of
the |χ(3)| spectra.
8
20
2
0
4
0
300
500
600
MEH-M3EH-PPV
2
0
0
1,05
300
400
500
600
25
4
Figure 5. Ratio of nTE and nTM of MEH-PPV, MEH-M3EHPPV and M3EH-PPV films.
10
5
5
0
300
The dispersions of the modulus of χ(3) at 1/3 of the
fundamental wavelength compared with linear absorption
spectra for all PPVs studied are displayed in Figure 6.
The χ(3) values exhibit a strong spectral dependence on
the laser wavelength λL because of three-photon
resonances with electronic states of the polymers. The
spectrum of the χ(3) resembles the linear absorption
coefficient: it has a maximum, denoted χ(3)max, at the
laser wavelength λL ≈ 3λmax of the absorption coefficient.
The strong maximum of χ(3)max is ascribed to a threephoton resonance with states located at the top of the
valence band and the exciton state. It occurs at
wavelength λL(χ(3)max) ≈ 3λmax of linear absorption
coefficient. The values of χ(3)max of all PPVs studied are
given in Table 1.
The peaks of χ(3) spectra of all-PPVs are red shifted
as compared to their λmax. These shifts are explained as a
consequence of the statistical distribution on the effective
π-conjugation length. As the second order molecular
hyperpolarizability, which is responsible for the process
of THG increases strongly with the conjugation length,
10
15
esu]
1100
-11
1000
[10
900
χ
800
Wavelength [nm]
-1
700
20
α [10 cm ]
600
120
15
M3EH-PPV
1,00
-11
(3)
4
5
χ
1,10
6
10
[10
8
15
esu]
-1
10
(3)
1,15
20
400
4
MEH-PPV
MEH-M3EH-PPV
M3EH-PPV
α [10 cm ]
Ratio of nTE/nTM
1,20
-11
5
[10
4
(3)
10
χ
6
-1
15
esu]
MEH-PPV
α [10 cm ]
to n, are both highly polarized and have their main
components in the chain direction of PPV. Consequently,
αmax and n are largest if the electric field of incident light
is parallel to the chain direction. If the PPV chains
become increasingly aligned parallel to the substrate
plane, it is evident that αmax which is measured at E
parallel to the film plane, and nTE will increase. This
behavior strongly indicates that amount of PPV chain
segments aligned parallel to the substrate plane in thin
film is increased in going from MEH-PPV, MEH-M3EHPPV and finally to M3EH-PPV. Recently, we observed
this effect in thin films of MEH-PPV, which were
prepared from different molecular weight, Mw. The chain
segments show an increased tendency to align parallel to
the layer plane with increasing Mw [8].
0
400
500
600
λ, λL/3 [nm]
Figure 6. Spectra of the modulus of χ(3) at λL/3 in comparison with
linear absorption spectra of thin films of MEH-PPV, MEH-M3EHPPV and M3EH-PPV.
As can be seen in Table 1, the χ(3) values is increased in
going from MEH-PPV, MEH-M3EH-PPV and M3EH-PPV
which might be indicated that a more ordered and planar
arrangement of the polymer chains was promoted in spin cast
film M3EH-PPV as discussed above. A planar arrangement of
the polymer chains is expected to enhance the nonlinear
optical response in force of the reduced dimensionality of the
π-electron delocalisation. This hypothesis of in-plane ordering
was also supported by the anisotropy as displayed in Figure 5.
Thin film prepared from M3EH-PPV showed the larger
refractive index and birefringence that that of MEH-PPV and
its copolymer, what is an indication of an increased ordering.
Our recent study shows that the third order susceptibility χ(3)
of thin films of MEH-PPV is increased with the orientation of
polymer chains parallel to the substrate [9]. The density of
polymer might be another factor that influence the χ(3) value.
Proc. of the 2nd International Conf. on Optics and Laser Applications
ICOLA’07, September 5-7, Yogyakarta, Indonesia
The waveguide propagation loss was determined by
measuring the stray light of TE modes as a function of
distance from the coupling prism. Figure 7 shows the
stray light at the diode array for MEH-PPV and MEHM3EH-PPV slab waveguides.
TE0 at 1064 nm
Intensity [a.u.]
10
3
MEH-PPV
MEH-M3EH-PPV
10
2
0,0
0,5
1,0
1,5
2,0
x [cm]
Figure 7. Intensity of the light scattered from TE0 modes of
waveguides of MEH-PPV and MEH-M3EH-PPV versus
distance from the prism at λ = 1064 nm.
IV. CONCLUSIONS
We have performed comparative studies of three polymer
films of PPV derivatives by means of reflectrometry, prism
coupler, third harmonic generation spectroscopy and
waveguide propagation loss. We have shown that the length of
alkyl side chains affects both the linear and nonlinear optical
properties as well as waveguide properties. The reduced
amount of alkyl-chains leads to an increase of the number πelectrons per unit volume, therefore, more polymer chain
segments are oriented parallel to the layer plane. As
consequences, the αmax, nTE , and χ(3) increase in the sequence
from MEH-PPV, MEH-M3EH-PPV to M3EH-PPV. However,
the reduced of alkyl-chains substitution reduce of solubility
which leads to the gel formation. Therefore, both αgw (TE0)
and αgw (TM0) are increased. We have concluded that thin
films of the conjugated polymers MEH-PPV is the most
appropriate candidate for all-optical switching applications,
because it exhibit good combination of large value of cubic
nonlinearity and ultimately low waveguide propagation loss
coefficient.
REFERENCES
The slopes of the lines fitted to the experimental data
yield the loss coefficients of the guided waves αgw. The
values of αgw of all PPVs both in TE- and TMpolarizations are presented in Table 1. They contain the
contributions of intrinsic absorption and the scattering
losses, which depend on the surface roughness of the
waveguide. Although the values of the relative surface
roughness (Ra/d) of all PPVs are comparable (0.5 –
1.2 %), they exhibit different values of αgw. This might
be related to aggregate formation caused by a different
solubility of the polymers. The substitution with the
branched 2-ethylhexyloxy group causes very good
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reduced in going from MEH-PPV to MEH-M3EH-PPV
and finally to M3EH-PPV due to the decrease of the
relative number of this “solubility providing” substituent
(Figure 1). Consequently, an increased tendency of
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PPVs. As a consequence, αgw in both TE and TM
polarizations increases. Another factor might be related
to the different morphology of the films. Our recent study
of thin films MEH-PPV shows that the large changes of
αgw can be caused by different morphology of thin films,
in particular on the arrangement of polymer chains in the
films [8].
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