Table Of Content9911447700..ccaasseewwrraapp..iinndddd 11 55//1199//0099 1111::3344 AAMM
Nonlinear Optics
of
Organic Molecules
Polymers
and
Edited by
Hari Singh Nalwa
Hitachi Research Laboratory
Hitachi Ltd.
Hitachi City, lbaraki, Japan
Seizo Miyata
Tokyo University ofA griculture and Technology
Kogenei, Tokyo, Japan
CRC Press
Boca Raton New York London Tokyo
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Senior Project Editor: Susan Fox
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Library of Congress Cataloging-in-Publication Data
Nonlinear optics of organic molecules and polymers I edited by Harl Singh Nalwa, Seizo Miyata.
p. cm.
Includes bibliographical references and index.
ISBN 0-8493-8923-2 (alk. paper)
I. Optoelectronics-Materials. 2. Nonlinear optics-Materials. 3. Organic compounds-Optical
properties. 4. Polymers-Optical properties. I. Nalwa, Harl Singh, 1954- . II. Miyata, Seizo, 1941-
TA1750.N658 1996
621.36'9-dc20 96-20281
CIP
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PREFACE
The field of nonlinear optics emerged three decades ago with the development of the first operating
laser and the demonstration of frequency doubling phenomena. These milestone discoveries not only
generated much interest in laser science, but also set the stage for future work on nonlinear optics. The
invention of lasers led to the discovery of interesting nonlinear optical phenomena in inorganic materials
and the development of structure-property relationships. Nonlinear optical effects in organic materials
were reported in the early 1970s, and the importance of novel materials was realized through theory,
models, and synthesis. The extraordinary growth and development of nonlinear optical materials during
the past decade has rendered photonic technologies an indispensable part of our daily life as we enter
the 21st century of the "Information Age." Our society will be benefited from advanced computer
networks and telecommunication systems that would bring photonics technology from infancy to maturity
probably within a decade. Recognizing the importance of photonic technology, this book covers all
aspects of nonlinear optics and contains a wealth of information related to computational analysis,
techniques, materials, and devices. With the emerging demand for information systems, nonlinear
optical materials have been considered the key elements for the future photonic technologies of optical
computing, telecommunications, optical interconnects, high density data storage, sensors, image pro
cessing, and switching. Considerable effort has been made to develop photonic devices from nonlinear
optical organic materials in research laboratories around the world.
The early texts dealt with the problems of setting up the targets of materials and devices through
identifying promising nonlinear optical materials for industrial applications, and understanding structure
property relationships. Finding answers to such problems stimulated much research work in novel
materials. These problems have been extensively addressed and views on nonlinear optical materials
and their based devices are clear now. The rapid growth of this field is evidenced by the several-fold
increase in the number of papers and patents published on nonlinear optics in the past few years. Organic
materials with sufficiently large optical nonlinearities have been identified to be practical in a variety
of photonic devices.
This book, written by leading experts in industry and academia, covers all aspects of nonlinear optics
in an in-depth and comprehensive manner; the scope ranges from modem computational analysis of
optical nonlinearities, through description of experimental techniques for measuring nonlinear optical
coefficients, and provides an in-depth coverage of advances in organic molecules and polymers. This
comprehensive text offers an interdisciplinary approach toward correlating molecular engineering with
optimization of optical nonlinearities. The field is multidisciplinary, as it needs expertise in computing,
chemistry, physics, material science, and optical engineering. During the past decade, the field of
nonlinear optics has developed remarkably and, in particular, there has been significant growth in the
past 6 to 7 years from the synthetic chemistry viewpoint. A wide range of excellent optical quality
single crystals is now available, through there is an increasing trend towards the use of organic polymers
as photonic components because of their ease of processing and fabrication; compatibility with metals,
ceramics, semiconductors; and glasses; good mechanical strength and flexibility to tailor nonlinear
optical properties; and material performance to specific end uses which make them fascinating materials
for applications. As a result, much progress on the materials front has been made since the recognition
of polymeric materials. This book illustrates in a clear and concise way the structure-property relationship
necessary to understand a wider range of organic and organometallic materials with exciting potential
for future photonic technologies. It emphasizes how novel organic superstructures can be tailored to
optimize nonlinear optical responses by carefully viewing the desired functions originating from the
chemical species. Owing to their versatility, organic materials have great potential because multifunctions
can be introduced by applying chemical strategies.
The state of the art in the field of nonlinear optics is presented by some of the most renowned
scientists in the world. An introduction to nonlinear optical phenomena is provided in Chapter 1 by
Garito and co-workers. The in-depth theoretical treatments of second-order optical nonlinearities are
presented in Chapter 2 by Morley and Pugh, in order to enable understanding of correlations between
molecular structures and second-order optical nonlinearities. In Chapter 3, Watanabe et al. describe
various measurement techniques for refractive index and, second-order nonlinear optical susceptibilities
measurements with powder methods, the phase-matching method, the Maker-fringe method, the SHEW
technique and molecular hyperpolarizabilities from the EFISH method and the HRS method. Nalwa et
al. provide a complete coverage of second-order NLO materials in Chapter 4, where many second
order NLO materials, including single crystals, guest-host systems, NLO dye-functionalized polymers,
polar polymers, Langmuir-Blodgett films, self-assembled multilayer systems, liquid crystals, and organo
metallic materials, are summarized. Applications of second-order NLO materials in photonic technologies
are also described. Phase-matched second harmonic generation of organic materials with phase-matching
techniques such as collinear and noncollinear phase matching in uniaxial and biaxial crystals and in
optical waveguides, mode dispersion-type phase matching, collinear-type phase matching, Crenkov
type phase matching, phase matching in periodically poled waveguides, are discussed in Chapter 5 by
Watanabe et al.
In Chapter 6, Bosshard and Giinter describe various measurement techniques for determining electro
optic coefficients and summarize organic single crystals and polymers for electro-optical applications.
Applications of EO polymers in optical modulators are discussed by Teng in Chapter 7. With the current
upsurge of interest in electro-optic devices, one can foresee the ultimate applications in coming years.
Future high-density optical storage systems that need short wavelengths are expected from organic NLO
materials. In Chapter 8, Kippelen, Meerholz, and Peyghambarian describe measurement techniques and
organic polymeric materials for photorefractive effects. Photorefractive materials are newly emerging
photonic elements with capabilities to store many holograms at a data rate of storage of a hundred
times faster than commercially available magnetic hard disks.
Nalwa provides the state-of-the-art reviews on quantum chemical approaches, measurement tech
niques, and organic materials for third-order nonlinear optics. Theoretical calculations of microscopic
third-order optical nonlinearities using empirical, semiempirical, and ab initio methods, a comparison
between different computational methods and theoretical and experimental results and the effects of
nature of 'IT-bonding sequence, delocalization length, donor-acceptor groups, conformation, symmetry,
dimensionality and charge-transfer complex formation on optical nonlinearities have been dealt with
in detail in Chapter 9. Chapter 10 describes the measurement techniques for third-order nonlinear optical
susceptibilities and second hyperpolarizabilities using third-harmonic generation (THG), degenerate
four-wave mixing (DFWM), four-wave mixing (FWM), optical Kerr gate (OKG), optical power limiter
(OPL), and Z-scan techniques. Third-order nonlinear optical effects are an indispensable molecular
property, therefore the studies vary to a great extent. Chapter 11 focuses on third-order NLO organic
materials with complete coverage of liquids, molecular solids (dyes, charge-transfer complexes, fuller
enes, hellicenes), 'IT-conjugated polymers, NLO-chromophore grafted polymers, organometallic com
pounds, NLO dyes and semiconductors doped polymers and glass composites, liquid crystals, and
biomaterials. Time-resolved spectroscopy to study the ultrafast nonlinear optical response and excited
state dynamics are also briefly discussed. Applications of organic NLO materials in third-order nonlinear
optics are discussed by Stegeman in Chapter 12. Perry provides an excellent description of optical
limiting phenomena in organic materials such as fullerenes, metallo-phthalocyanines, porphyrins, and
other dyes in Chapter 13. The applications of optical limiting materials are discussed in Chapter 14 by
Van Stryland and co-workers.
Nonlinear optics is now established as one of the best alternatives to electronics for the future
photonic technologies. This book presents an overview of the exciting new advances in nonlinear optical
materials and their industrial applications. It will provide a useful reference for graduate and advanced
undergraduate students as well as researchers, scientists, and engineers in solid-state physics, materials
science, chemistry, electrical, optical, fiber and polymer engineering, and computational science.
The editors wish to express gratitude to all contributors for sharing their knowledge and expertise
in the field of nonlinear optics by submitting excellent manuscripts which made this book a reality.
Their efforts deserve appreciation as these contributors are the pillars of this novel foundation. At
Hitachi Research Laboratory, Dr. H. S. Nalwa gratefully acknowledges the support of Dr. Akio Mukoh,
a connoisseur of many aspects of nonlinear optics, who has inspired many of us in this field of science
and who whole-heartedly encouraged the writing of this monograph. He would also like to thank Drs.
Atsushi Kakuta, T. Iwayanagi, Akio Takahashi, M. Isogai, M. Sagawa, T. Nakayama, Y. Imanishi, T.
Hamada, S. Ishihara, and R. Inaba at Hitachi Research Laboratory for their continuous support and
cooperation. Drs. A. Ticktin, K. H. Hass, and A. Esser of BASF are especially acknowledged for their
valuable comments and generosity in providing several original illustrations. Professor M. Poplodous
kindly read the computational evaluation of third-order optical nonlinearity and provided useful com
ments. Dr. Nalwa is also very grateful to Professor Richard T. Keys of California State University at
Los Angeles for critically reading some manuscripts and for his valuable comments and to Dr. Toshiyuki
Watanabe of Tokyo University of Agriculture and Technology for his tremendous help in compiling
this monograph. Dr. Nalwa would also like to acknowledge Professor Padma Vasudevan, Professor
Prem Vrat, and Professor R. P. Dahiya of Indian Institute of Technology in New Delhi and Professor
Satya Vir Arya of C. C. R. College at Muzaffarnagar for their continuous support. Thanks are also due
to Sri Ram Singh, Jiley Singh, Kadam Singh, Braham Singh, Sardar Singh, Jagmer Singh, Dharam Pal
Singh, Ranvir Singh Chaudhary, Yash Pal Singh, Braj Pal Singh, Satyendra Singh, Ashish Kumar,
Bhanwar Singh, and Arvind Kumar, and to his friends, Yogesh Malik, Krishi Pal Raghuvanshi, Rakesh
Misra, Deepak Singhal, Michael McMurray, Dr. Dharam Pal Singh, Dr. V. B. Reddy, Professor G. K.
Surya Prakash, and Dr. Claus Jessen, for their continuous encouragements. Dr. Nalwa would like to
acknowledge the cooperation and patience of his wife Dr. Beena Singh Nalwa for her understanding
while writing manuscripts during the evenings, weekends and holidays at home and in lessening entropy
from my kids, Surya and Ravina. Dr. Nalwa gratefully acknowledges the editiorial support of Betsy
Winship of lnnodata Corporation. Finally, the assistance of the staff members at CRC Press who helped
in this project is gratefully acknowledged.
Harl Singh Nalwa
Seizo Miyata
THE EDITORS
Harl Singh Nalwa is a Research Scientist in the Materials Department at the Hitachi Research Laboratory,
Hitachi Ltd., Japan. Dr. Nalwa is also an Honorary Professor at the Indian Institute of Technology in
New Delhi. He has edited several books: Ferroelectric Polymers (1995), Organic Electroluminescent
Materials and Devices (1996), and Handbook of Organic Conductive Molecules and Polymers (1997),
Vols. 1-4. He has authored over 100 scientific publications in leading refereed journals and has 18
Japanese patents either applied for or issued on electronics and photonics materials and devices. He
serves on the editorial board of Applied Organometallic Chemistry, Journal ofM acromolecular Science
Physics, and Photonics Science News, and is a member of the American Chemical Society and American
Association for the Advancement of Science. He has been awarded a number of prestigious fellowships
in India and abroad. He was a guest scientist at Hahn-Meitner Institute in Berlin, Germany (1983),
Research Associate at University of Southern California in Los Angeles (1984-1987), and lecturer at
Tokyo University of Agriculture and Technology in Tokyo, Japan (1988-1990). He has been working
with Hitachi Ltd since 1990. Dr. Nalwa received a B.Sc. degree (1974) in biosciences from the Meerut
University, a M. Sc. degree (1977) in organic chemistry from the University of Roorkee, and a Ph.D.
degree (1983) in polymer science from the Indian Institute of Technology in New Delhi, India.
Seizo Miyata is the Dean and Professor of the Graduate School of Bio-applications and Systems
Engineering at the Tokyo University of Agriculture and Technology. He has more than 200 patents and
150 scientific publications on electronics and photonics materials and devices to his credit. He has
authored/edited several books: in Japanese: Experimental Techniques of Polymeric Materials (1981),
Chemistry ofP olymeric Materials (1982), World ofM odem Science (1986), Intelligent Materials (1987),
and Photonics (1995); and in English: Organic Electroluminescent Materials and Devices (1996).
Professor Miyata serves on the editorial board of Supramolecular Science, Polymer Journal, and
International Journal of Nonlinear Optical Physics. He is the Vice President of the Polymer Society
of Japan, and is a member of the Japanese Science Council. He has organized and presided over 15
national and international conferences. He is a leader of the national project in Japan on lightwave
manipulation using organic materials and belongs to the Ministry of Education in Japan, and he has
received an award from the Polymer Society of Japan on the discovery of novel piezoelectric polymers.
He was a guest professor at California Institute of Technology in Pasadena, USA (1982-1983) and a
guest scientist at AT&T Bell Laboratories (1984). He has been working with Tokyo University of
Agriculture and Technology since 1969. Professor Miyata received a B. Sc. degree (1964) in sciences
from the Tokyo Educational University and a Ph.D. degree (1969) in polymer science from the Tokyo
Institute of Technology.
CONTRIBUTORS
Christian Bosshard N. Peyghambarian
Nonlinear Optics Laboratory Optical Sciences Center and
Institute of Quantum Electronics Materials Science and Engineering Department
Eidgenossische Technische Hochschule (ETH) University of Arizona
CH-8093 Zurich, Switzerland Tucson, Arizona 85721, USA
A. F. Garito David Pugh
Department of Physics and Astronomy Department of Pure and Applied Chemistry
University of Pennsylvania University of Strathclyde
Philadelphia, Pennsylvania 19104-6396, USA Glasgow, G 1 IXL, UK
Peter Gunter A. A. Said
Nonlinear Optics Laboratory Center for Research and Education in Optics
Institute of Quantum Electronics and Lasers (CREOL)
Eidgenossische Technische Hochschule (ETH) University of Central Florida
CH-8093 Zurich, Switzerland Orlando, Florida 32826, USA
D. J. Hagan George I. Stegeman
Center for Research and Education in Optics Center for Research and Education in Optics
and Lasers (CREOL) and Lasers (CREOL)
University of Central Florida University of Central Florida
Orlando, Florida 32826, USA Orlando, Florida 32826, USA
B. Kippelen Chia-Chi Teng
Optical Sciences Center and Hoechst Celanese Corporation
Materials Science and Engineering Department Robert L. Mitchell Technical Center
University of Arizona 86 Morris Avenue
Tucson, Arizona 85721, USA Summit, New Jersey 07901, USA
K. Meerholz Eric W. Van Stryland
Optical Sciences Center and Center for Research and Education in Optics
Materials Science and Engineering Department and Lasers (CREOL)
University of Arizona University of Central Florida
Tucson, Arizona 85721, USA Orlando, Florida 32826, USA
Seizo Miyata Toshiyuki Watanabe
Graduate School of Bio-applications and Department of Applied Chemistry
Systems Engineering Tokyo University of Agriculture and Technology
Tokyo University of Agriculture and Technology Koganei, Tokyo 184, Japan
Koganei, Tokyo 184, Japan
K. Y. Wong
John 0. Morley Department of Physics
Chemistry Department Chinese University of Hong Kong
University of Wales, Swansea Shatin, N. T., Hong Kong
Swansea, SA2 8PP, UK
T. Xia
Hari Singh Nalwa Center for Research and Education in Optics
Hitachi Research Laboratory, Hitachi Ltd., and Lasers (CREOL)
7-1-1 Ohmika-cho University of Central Florida
Hitachi City, Ibaraki 319-12, Japan Orlando, Florida 32826, USA
Joseph W. Perry Y.Z. Yu
Jet Propulsion Laboratory SEQ Ltd.
California Institute of Technology 181 Cherry Valley Road
4800 Oak Grove Drive Princeton, New Jersey 08540, USA
Pasadena, California 91109, USA
CONTENTS
Chapter 1
Introduction to Nonlinear Optics ........................................................................................................ 1
Y. Z. Yu, K. Y. Wong, and A. F. Garito
Chapter 2
Computational Evaluation of Second-Order Optical Nonlinearities ................................................. 29
John 0. Morley and David Pugh
Chapter 3
Measurement Techniques for Refractive Index and Second-Order Optical Nonlinearities .............. 57
Toshiyuki Watanabe, Bari Singh Nalwa, and Seizo Miyata
Chapter 4
Organic Materials for Second-Order Nonlinear Optics ..................................................................... 89
Bari Singh Nalwa, Toshiyuki Watanabe, and Seizo Miyata
Chapter 5
Phase-Matched Second Harmonic Generation in Organic Materials ................................................ 351
Toshiyuki Watanabe, Bari Singh Nalwa, and Seizo Miyata
Chapter 6
Electro-optic Effects in Molecular Crystals and Polymers ................................................................ 391
Christian Bosshard and Peter Giinter
Chapter 7
High-Speed Electro-optic Modulators from Nonlinear Optical Polymers ........................................ 441
Chia-Chi Teng
Chapter 8
An Introduction to Photorefractive Polymers ......... ......... ........ .. ...... ......... ..... ........ ..... .............. ......... 465
B. Kippelen, K. Meerholz, and N. Peyghambarian
Chapter 9
Computational Evaluation of Third-Order Optical Nonlinearities .................................................... 515
Bari Singh Nalwa
Chapter 10
Measurement Techniques for Third-Order Optical Nonlinearities .................................................... 571
Harl Singh Nalwa
Chapter 11
Organic Materials for Third-Order Nonlinear Optics ........................................................................ 611
Bari Singh Nalwa
Chapter 12
Applications of Organic Materials in Third-Order Nonlinear Optics ............................................... 799
George I. Stegeman
Chapter 13
Organic and Metal-Containing Reverse Saturable Absorbers for Optical Limiters ......................... 813
Joseph W. Perry
Chapter 14
Applications of Nonlinear Optics to Passive Optical Limiting ......................................................... 841
Eric W. Van Stryland, D. J. Hagan, T. Xia, and A. A. Said
Index .................................................................................................................................................... 861
