Table Of ContentSilicon Nanophotonics
Basic Principles, Present Status and Perspectives
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Silicon
Nanophotonics
Basic Principles, Present Status and Perspectives
Editor
Leonid Khriachtchev
University of Helsinki, Finland
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Published by
World Scientific Publishing Co. Pte. Ltd.
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A catalogue record for this book is available from the British Library.
SILICON NANOPHOTONICS
Basic Principles, Present Status and Perspectives
Copyright © 2009 by World Scientific Publishing Co. Pte. Ltd.
All rights reserved. This book, or parts thereof, may not be reproduced in any form or by any means,
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ISBN-13 978-981-4241-11-3
ISBN-10 981-4241-11-3
Printed in Singapore.
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To my daughters
Vera and Ksenia, with love
Leonid
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PREFACE
Nanoscience is a rapidly developing area of research which promises a
lot in physics, chemistry, and medicine, and some of the ideas have been
already realized. Nanoscale materials are particularly interesting for
photonics, which can be defined as the science and technology of light.
Photonics supplements electronics in the form of optoelectronics, and it
is considered as one of the key technology areas of the 21st century.
Silicon is the leading material for electronics; hence integration of all
optical functions into silicon technology is practically very important and
widely recognized as a great challenge. This book combines the concepts
of nanoscience, photonics, and silicon technology. A lot of research
activity has been carried out in these fields, and it is impossible to
cover all aspects. Our book presents a special viewpoint of Silicon
Nanophotonics, and the content is mainly limited by photonic properties
of silicon nanocrystals and by closely related topics. We believe that
silicon nanocrystals offer a promising practical perspective for photonics
and the related materials are exciting also from the fundamental and
educational points of view.
Research on silicon nanocrystals was strongly activated by Leigh
T. Canham who discovered in 1991 bright visible emission from porous
silicon. Very many studies have been devoted to understanding of
the light-emission mechanisms and a number of models have been
suggested. An important opinion was published by Philippe Fauchet and
co-workers in 1999 when they provided strong arguments in favor of
surface origin of the light emission from oxidized porous silicon. Light
amplification (optical gain) in silicon nanocrystals in silica was reported
first by an Italian research group led by Lorenzo Pavesi. Indeed,
generation of light in silicon is a challenging perspective; however, the
issue of a laser and other light emitting devices limits neither the activity
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in the field nor the contents of this book. The studies cover light
modulators, optical waveguides and interconnectors, optical amplifiers,
detectors, memory elements, etc.
The present book collects recent results of a number of groups
worldwide. The contributors of our book work in United States, Japan,
and eight European countries. The book contents include: (i) Basic
principles of the most important photonic elements based on silicon
nanocrystals; (ii) Theoretical analysis of optical properties, light
emission and optical gain of silicon nanocrystals; (iii) Experimental
studies of the most important phenomena and optoelectronic properties
of silicon nanocrystals such as light emission, optical gain and lasing,
structure, optical properties, optical waveguiding, optical and electrical
memory. The experimental results are illustrated by simple modeling;
(iv) Experimental methods (transmission electron microscopy, Raman
spectroscopy, etc.), preparation technique (molecular beam deposition,
laser ablation, ion implantation, etc.), and sample architecture (silicon-
rich silicon oxide films, Si/SiO superlattices, free-standing films)
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described in appropriate places; (v) Silicon-based material with
additional doping (Er-doped silicon nanocrystals and SiN materials) and
single silicon dots; (vi) Perspective applications and some related topics.
The authors present rich bibliography helping further reading. Some
overlap between the chapters is inevitable; however, this allows the
chapters to be understood independently. Some differences in opinions
and interpretations between the authors can be found, which is also
understandable for this hot and quickly developing field. In any case, we
have tried to indicate in our book where the field is now and where it is
going. We hope that this information will be useful for a broad
readership including young researchers coming to the field of
nanoscience and nanotechnology.
The Editor thanks all contributors for accepting his invitation to
participate in the book and writing exciting stories.
Leonid Khriachtchev
Editor
January 21, 2008
CONTENTS
Preface vii
Chapter 1 Silicon Nanocrystals Enabling Silicon Photonics 1
Nicola Daldosso and Lorenzo Pavesi
1. The Need of a Silicon Photonics............................... 1
1.1. Silicon Photonics.............................................. 2
1.1.1. Waveguides.......................................... 3
1.1.2. Modulators............................................ 4
1.1.3. Sources................................................. 5
1.1.4. Detectors............................................... 6
2. Nanosilicon for Photonics......................................... 7
2.1. Si-nc waveguides.............................................. 7
2.2. Non-linear effects: fast optical switches.......... 9
2.3. Light emission and optical gain in Si
nanocrystals...................................................... 11
2.4. Si nanocrystals LEDs....................................... 12
2.5. Er coupled to nano-Si for optical amplifiers.... 14
2.6. Carrier absorption within Si nanocrystals
waveguides....................................................... 17
3. Conclusions .............................................................. 20
References...................................................................... 20
Chapter 2 Theoretical Studies of Absorption, Emission and
Gain in Silicon Nanostructures 25
Elena Degoli, Roberto Guerra, Federico Iori,
Rita Magri, Ivan Marri, and Stefano Ossicini
1. Introduction .............................................................. 26
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