Micro- and Nanophotonic Technologies E-Book

Patrick Meyrueis

• Herausgeber: Wiley-VCH Verlag GmbH & Co. KGaA
• Kategorie: Fachliteratur
• Serie: Nanotechnology Innovation & Applications
• Sprache: Englisch

Seitenzahl: 959

Veröffentlichungsjahr: 2017

Beschreibung

Edited and authored by leading experts from top institutions in Europe, the US and Asia, this comprehensive overview of micro- and nanophotonics covers the physical and chemical fundamentals, while clearly focusing on the technologies and applications in industrial R&D.
As such, the book reports on the four main areas of telecommunications and display technologies; light conversion and energy generation; light-based fabrication of materials; and micro- and nanophotonic devices in metrology and control.

Leseprobe

Contents

Cover

Further Volumes of the Series “Nanotechnology Innovation & Applications”

Title Page

Copyright

Dedication

Series Editor Preface

About the Series Editor

Foreword

Preface

An Overview of Micro- and Nanophotonic Science and Technology

1 Global Scale of the Subject

2 A Brief History

3 Characteristics

4 Prospects and Outlook

Acknowledgment

References

Part One: From Research to Application

Chapter 1: Nanophotonics: From Fundamental Research to Applications

1.1 Introduction

1.2 Application of Photonic Crystals to Solar Cells

1.3 Antireflecting Periodic Structures

1.4 Black Silicon

1.5 Metamaterials for Wide-Band Filtering

1.6 Rough Surfaces with Controlled Statistics

1.7 Enhancement of Absorption in Organic Solar Cells with Plasmonic Nano Particles

1.8 Quantum Dot Solar Cells

1.9 Conclusions

References

Chapter 2: Photonic Crystal and Plasmonic Microcavities

2.1 Introduction

2.2 Photonic Crystal Microcavity

2.3 Purcell Effect

2.4 Plasmonic Microcavity

References

Chapter 3: Unconventional Thermal Emission from Photonic Crystals

3.1 Introduction

3.2 3D Photonic Crystals

3.3 2D Photonic Crystals

3.4 1D Photonic Crystals

3.5 Summary

References

Chapter 4: Extremely Small Bending Loss of Organic Polaritonic Fibers

4.1 Introduction

4.2 Exciton–Polariton Waveguiding in TC Nanofibers

4.3 Miniaturized Photonic Circuit Components Constructed from TC Nanofibers

4.4 Theoretical Analysis

References

Chapter 5: Plasmon Color Filters and Phase Controllers

5.1 Introduction

5.2 Optical Filter Based on Surface Plasmon Resonance

5.3 Transmission Phase Control by Stacked Metal-Dielectric Hole Array

5.4 Summary

References

Chapter 6: Entangled Photon Pair Generation in Naturally Symmetric Quantum Dots Grown by Droplet Epitaxy

6.1 Introduction

6.2 Quantum Dot Photon-pair Source

6.3 Natural Growth of Symmetric Quantum Dots

6.4 Droplet Epitaxy of GaAs Quantum Dots on AlGaAs(1 1 1)A

6.5 Characterization of Entanglement

6.6 Violation of Bell's Inequality

6.7 Quantum-state Tomography and Other Entanglement Measures

References

Chapter 7: Single-Photon Generation from Nitrogen Isoelectronic Traps in III–V Semiconductors

7.1 Introduction

7.2 What is Isoelectronic Trap?

7.3 GaP:N Case

7.4 GaAs:N Case

7.5 Summary

References

Chapter 8: Parity–Time Symmetry in Free Space Optics

8.1 Parity–Time Symmetry in Diffractive Optics

8.2 Free Space Diffraction on Active Gratings with Balanced Phase and Gain/Loss Modulations

8.3 PT-Symmetric Volume Holograms in Transmission Mode

8.4 Analysis of Unidirectional Nonparaxial Invisibility of Purely Reflective PT-Symmetric Volume Gratings

8.5 Summary and Conclusions

References

Chapter 9: Parity–Time Symmetric Cavities: Intrinsically Single-Mode Lasing

9.1 Introduction

9.2 Resonant Cavities Based on two PT-Symmetric Diffractive Gratings

9.3 Distributed Bragg Reflector Structures Based on PT-Symmetric Coupling with Lowest Possible Lasing Threshold

9.4 Unique Optical Characteristics of a Fabry–Perot Resonator with Embedded PT-Symmetrical Grating

9.5 Summary and Conclusions

References

Chapter 10: Silicon Quantum Dot Composites for Nanophotonics

10.1 Introduction

10.2 Core–Shell Type Nanocomposites

10.3 Polymer Encapsulation

10.4 Micelle Encapsulation

10.5 Summary

Acknowledgments

References

Part Two: Breakthrough Applications

Chapter 11: Ultrathin Polarizers and Waveplates Made of Metamaterials

11.1 Concept and Practice of Subwavelength Optical Devices

11.2 Ultrathin Polarizers

11.3 Ultrathin Waveplates

11.4 Constructions of Functional Subwavelength Devices

11.5 Summary and Prospects

Acknowledgments

References

Chapter 12: Nanoimprint Lithography for the Fabrication of Metallic Metasurfaces

12.1 Introduction

12.2 UV-NIL

12.3 Large-Area SP-RGB Color Filter Using UV-NIL

12.4 Emission-Enhanced Plasmonic Metasurfaces Fabricated by NIL

12.5 Metasurface Thermal Emitters for Infrared CO2 Detection by UV-NIL

12.6 Summary

References

Chapter 13: Applications to Optical Communication

13.1 Introduction

13.2 Optical Fiber and Propagation Impairments

13.3 Basics of Functional Devices

13.4 Advanced Optical Communication Techniques

13.5 Today's Optical Communication Systems

13.6 Today's Challenges and Perspectives

Acknowledgments

List of Acronyms and Abbreviations

References

Chapter 14: Advanced Concepts for Solar Energy

14.1 Introduction

14.2 Photon Management

14.3 Spectral Optimization

14.4 Advanced Concepts

14.5 Conclusions

References

Chapter 15: The Micro- and Nanoinvestigation and Control of Physical Processes Using Optical Fiber Sensors and Numerical Simulations: a Mathematical Approach

15.1 Introduction

15.2 Temperature Measurement and Heat Transfer Evaluation in a Circular Cylinder by Considering a High Accurate Numerical Solution

15.3 Numerical Analysis of the Diffusive Mass Transport in Brain Tissues with Applications to Optical Sensors

Acknowledgment

References

Chapter 16: Laser Micronanofabrication

16.1 Introduction

16.2 Physical Issues

16.3 Recent Technological Advances

16.4 Laser Microprocesses

16.5 Conclusions

References

Chapter 17: Ultrarealistic Imaging Based on Nanoparticle Recording Materials

17.1 Introduction

17.2 Preperation of Silver Hailde Emulsions: Principle

17.3 Testing of the Emulsion

17.4 Recording Museum Artifacts with Color Holography

17.5 Conclusions

Acknowledgments

References

Chapter 18: An Introduction to Tomographic Diffractive Microscopy: Toward High-Speed Quantitative Imaging Beyond the Abbe Limit

18.1 Introduction

18.2 Conventional Transmission Microscopy

18.3 Phase Amplitude Microscopy

18.4 Tomographic Diffractive Microscopy for True 3D Imaging

18.5 Biological Applications

18.6 Conclusions

References

Chapter 19: Nanoplasmonic Guided Optic Hydrogen Sensor

19.1 Introduction

19.2 Fiber Optic Sensor

19.3 Pd Hydrogen Sensing Systems

19.4 Fiber Optic Hydrogen Sensors

19.5 Fiber Surface Plasmon Resonance Sensor

19.6 Sensitive Material for Hydrogen Sensing

19.7 Conclusions

Acknwoledgment

References

Chapter 20: Fiber Optic Liquid-Level Sensor System for Aerospace Applications

20.1 Introduction

20.2 The Operation Principle and System Design

20.3 Experimental Results

20.4 Liquid-Level Sensor Performance

20.5 Conclusions

References

Chapter 21: Tunable Micropatterned Colloid Crystal Lasers

21.1 Introduction

21.2 Synthesis of Colloidal Microparticles and Reflection Features of CCs

21.3 Laser Action from CCs with Light-Emitting Planar Defects

21.4 Micropatterned Laser Action from CCs by Photochromic Reaction

21.5 Tunable Laser Action from CC Gel Films Stabilized by Ionic Liquid

21.6 Conclusions and Outlook

Acknowledgments

References

Chapter 22: Colloidal Photonic Crystals Made of Soft Materials: Gels and Elastomers

22.1 Introduction

22.2 Colloidal Photonic Crystal Gels Consist of Nonclose-packed Particles

22.3 Colloidal Photonic Crystal Elastomer Consists of Close-packed Particles

22.4 Applications

22.5 Summary and Outlook

References

Chapter 23: Surveying the Landscape and the Prospects in Nanophotonics

23.1 Retrospective

23.2 Fundamental Developments

23.3 Futorology

23.4 Applications

23.5 Summing Up

Index

End User License Agreement

List of Tables

Table 13.1

Table 13.2

Table 14.1

Table 14.2

Table 14.3

Table 15.1

Table 19.1

Table 19.2

Table 19.3

Table 20.1

List of Illustrations

Figure 1.1

Figure 1.2

Figure 1.3

Figure 1.4

Figure 1.5

Figure 1.6

Figure 1.7

Figure 1.8

Figure 1.9

Figure 1.10

Figure 1.11

Figure 1.12

Figure 1.13

Figure 1.14

Figure 1.15

Figure 1.16

Figure 1.17

Figure 1.18

Figure 1.19

Figure 1.20

Figure 1.21

Figure 1.22

Figure 1.23

Figure 1.24

Figure 1.25

Figure 1.26

Figure 1.27

Figure 1.28

Figure 2.1

Figure 2.2

Figure 2.3

Figure 2.4

Figure 2.5

Figure 2.6

Figure 2.7

Figure 2.8

Figure 2.9

Figure 2.10

Figure 2.11

Figure 3.1

Figure 3.2

Figure 3.3

Figure 3.4

Figure 3.5

Figure 3.6

Figure 3.7

Figure 3.8

Figure 3.9

Figure 3.10

Figure 4.1

Figure 4.2

Figure 4.3

Figure 4.4

Figure 4.5

Figure 4.6

Figure 4.7

Figure 4.8

Figure 4.9

Figure 4.10

Figure 4.11

Figure 4.12

Figure 4.13

Figure 4.14

Figure 5.1

Figure 5.2

Figure 5.3

Figure 5.4

Figure 5.5

Figure 5.6

Figure 5.7

Figure 5.8

Figure 5.9

Figure 5.10

Figure 5.11

Figure 5.12

Figure 5.13

Figure 5.14

Figure 5.15

Figure 5.16

Figure 5.17

Figure 5.18

Figure 5.19

Figure 5.20

Figure 5.21

Figure 5.22

Figure 5.23

Figure 6.1

Figure 6.2

Figure 6.3

Figure 6.4

Figure 6.5

Figure 6.6

Figure 6.7

Figure 6.8

Figure 6.9

Figure 6.10

Figure 6.11

Figure 6.12

Figure 6.13

Figure 6.14

Figure 6.15

Figure 7.1

Figure 7.2

Figure 7.3

Figure 7.4

Figure 7.5

Figure 7.6

Figure 7.7

Figure 7.8

Figure 7.9

Figure 8.1

Figure 8.2

Figure 8.3

Figure 8.4

Figure 8.5

Figure 8.6

Figure 8.7

Figure 8.8

Figure 8.9

Figure 8.10

Figure 8.11

Figure 8.12

Figure 8.13

Figure 8.14

Figure 8.15

Figure 8.16

Figure 8.17

Figure 8.18

Figure 8.19

Figure 8.20

Figure 8.21

Figure 8.22

Figure 8.23

Figure 8.24

Figure 8.25

Figure 8.26

Figure 8.27

Figure 8.28

Figure 8.29

Figure 9.1

Figure 9.2

Figure 9.3

Figure 9.4

Figure 9.5

Figure 9.6

Figure 9.7

Figure 9.8

Figure 9.9

Figure 9.10

Figure 9.11

Figure 9.12

Figure 9.13

Figure 9.14

Figure 9.15

Figure 9.16

Figure 9.17

Figure 9.18

Figure 9.19

Figure 9.20

Figure 9.21

Figure 10.1

Figure 10.2

Figure 10.3

Figure 10.4

Figure 10.5

Figure 10.6

Figure 10.7

Figure 10.8

Figure 11.1

Figure 11.2

Figure 11.3

Figure 11.4

Figure 11.5

Figure 11.6

Figure 11.7

Figure 11.8

Figure 11.9

Figure 11.10

Figure 11.11

Figure 11.12

Figure 12.1

Figure 12.2

Figure 12.3

Figure 12.4

Figure 12.5

Figure 12.6

Figure 12.7

Figure 12.8

Figure 12.9

Figure 12.10

Figure 12.11

Figure 12.12

Figure 13.1

Figure 13.2

Figure 13.3

Figure 13.4

Figure 13.5

Figure 13.6

Figure 13.7

Figure 13.8

Figure 13.9

Figure 13.10

Figure 13.11

Figure 13.12

Figure 13.13

Figure 13.14

Figure 13.15

Figure 13.16

Figure 14.1

Figure 14.2

Figure 14.3

Figure 14.4

Figure 14.5

Figure 14.6

Figure 14.7

Figure 14.8

Figure 15.1

Figure 15.2

Figure 15.3

Figure 15.4

Figure 15.5

Figure 15.6

Figure 15.7

Figure 15.8

Figure 15.9

Figure 15.10

Figure 15.11

Figure 15.12

Figure 15.13

Figure 15.14

Figure 15.15

Figure 15.16

Figure 15.17

Figure 15.18

Figure 15.19

Figure 15.20

Figure 15.21

Figure 15.22

Figure 15.23

Figure 15.24

Figure 15.25

Figure 16.1

Figure 16.2

Figure 16.3

Figure 16.4

Figure 16.5

Figure 16.6

Figure 16.7

Figure 16.8

Figure 16.9

Figure 16.10

Figure 16.11

Figure 16.12

Figure 16.13

Figure 16.14

Figure 16.15

Figure 16.16

Figure 16.17

Figure 16.18

Figure 17.1

Figure 17.2

Figure 17.3

Figure 17.4

Figure 17.5

Figure 17.6

Figure 17.7

Figure 17.8

Figure 17.9

Figure 17.10

Figure 17.11

Figure 17.12

Figure 17.13

Figure 18.1

Figure 18.2

Figure 18.3

Figure 18.4

Figure 18.5

Figure 18.6

Figure 18.7

Figure 19.1

Figure 19.2

Figure 19.3

Figure 19.4

Figure 19.5

Figure 19.6

Figure 19.7

Figure 19.8

Figure 19.9

Figure 19.10

Figure 19.11

Figure 19.12

Figure 20.1

Figure 20.2

Figure 20.3

Figure 20.4

Figure 20.5

Figure 20.6

Figure 20.7

Figure 20.8

Figure 20.9

Figure 20.10

Figure 20.11

Figure 20.12

Figure 20.13

Figure 20.14

Figure 20.15

Figure 20.16

Figure 20.17

Figure 21.1

Figure 21.2

Figure 21.3

Figure 21.4

Figure 21.5

Figure 21.6

Figure 21.7

Figure 21.8

Figure 22.1

Figure 22.2

Figure 22.3

Figure 22.4

Figure 22.5

Figure 22.6

Figure 22.7

Figure 22.8

Figure 22.9

Figure 22.10

Figure 22.11

Figure 22.12

Figure 22.13

Figure 22.14

Figure 22.15

Figure 22.16

Guide

Cover

Table of Contents

Begin Reading

Part 1

Chapter 1

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Further Volumes of the Series “Nanotechnology Innovation & Applications”

Axelos, M. A. V. and Van de Voorde, M. (eds.)

Nanotechnology in Agriculture and Food Science

2017

Print ISBN: 9783527339891

Cornier, J., Kwade, A., Owen, A., Van de Voorde, M. (eds.)

Pharmaceutical Nanotechnology

Innovation and Production

2017

Print ISBN: 9783527340545

Fermon, C. and Van de Voorde, M. (eds.)

Nanomagnetism

Applications and Perspectives

2017

Print ISBN: 9783527339853

Mansfield, E., Kaiser, D. L., Fujita, D., Van de Voorde, M. (eds.)

Metrology and Standardization for Nanotechnology

Protocols and Industrial Innovations

2017

Print ISBN: 9783527340392

Müller, B. and Van de Voorde, M. (eds.)

Nanoscience and Nanotechnology for Human Health

2017

Print ISBN: 978-3-527-33860-3

Puers, R., Baldi, L., van Nooten, S. E., Van de Voorde, M. (eds.)

Nanoelectronics

Materials, Devices, Applications

2017

Print ISBN: 9783527340538

Raj, B., Van de Voorde, M., Mahajan, Y. (eds.)

Nanotechnology for Energy Sustainability

2017

Print ISBN: 9783527340149

Sels, B. and Van de Voorde, M. (eds.)

Nanotechnology in Catalysis

Applications in the Chemical Industry, Energy Development, and Environment Protection

2017

Print ISBN: 9783527339143

Edited by Patrick Meyrueis, Kazuaki Sakoda, and Marcel Van de Voorde

Micro- and Nanophotonic Technologies

All books published by Wiley-VCH are carefully produced. Nevertheless, authors, editors, and publisher do not warrant the information contained in these books, including this book, to be free of errors. Readers are advised to keep in mind that statements, data, illustrations, procedural details or other items may inadvertently be inaccurate.

Library of Congress Card No.: applied for

British Library Cataloguing-in-Publication DataA catalogue record for this book is available from the British Library.

Bibliographic information published bythe Deutsche NationalbibliothekThe Deutsche Nationalbibliothek lists this publication in the Deutsche Nationalbibliografie; detailed bibliographic data are available on the Internet at <http://dnb.d-nb.de>.

© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Boschstr. 12, 69469 Weinheim, Germany

All rights reserved (including those of translation into other languages). No part of this book may be reproduced in any form – by photoprinting, microfilm, or any other means – nor transmitted or translated into a machine language without written permission from the publishers. Registered names, trademarks, etc. used in this book, even when not specifically marked as such, are not to be considered unprotected by law.

Print ISBN: 978-3-527-34037-8ePDF ISBN: 978-3-527-69993-3ePub ISBN:978-3-527-69995-7Mobi ISBN: 978-3-527-69996-4oBook ISBN: 978-3-527-69994-0

Thanks to my wife for her patience with me spending many hours working on the book series through the nights and over weekends. The assistance of my son Marc Philip related to the complex and large computer files with many sophisticated scientific figures is also greatly appreciated.

Marcel Van de Voorde

Series Editor Preface

Since years, nanoscience and nanotechnology have become particularly an important technology areas worldwide. As a result, there are many universities that offer courses as well as degrees in nanotechnology. Many governments including European institutions and research agencies have vast nanotechnology programmes and many companies file nanotechnology-related patents to protect their innovations. In short, nanoscience is a hot topic!

Nanoscience started in the physics field with electronics as a forerunner, quickly followed by the chemical and pharmacy industries. Today, nanotechnology finds interests in all branches of research and industry worldwide. In addition, governments and consumers are also keen to follow the developments, particularly from a safety and security point of view.

This books series fills the gap between books that are available on various specific topics and the encyclopedias on nanoscience. This well-selected series of books consists of volumes that are all edited by experts in the field from all over the world and assemble top-class contributions. The topical scope of the book is broad, ranging from nanoelectronics and nanocatalysis to nanometrology. Common to all the books in the series is that they represent top-notch research and are highly application-oriented, innovative, and relevant for industry. Finally they collect a valuable source of information on safety aspects for governments, consumer agencies and the society.

The titles of the volumes in the series are as follows:

Human-related nanoscience and nanotechnology

Nanoscience and Nanotechnology for Human Health

Pharmaceutical Nanotechnology

Nanotechnology in Agriculture and Food Science

Nanoscience and nanotechnology in information and communication

Nanoelectronics

Micro- and Nanophotonic Technologies

Nanomagnetism: Perspectives and Applications

Nanoscience and nanotechnology in industry

Nanotechnology for Energy Sustainability

Metrology and Standardization of Nanomaterials

Nanotechnology in Catalysis: Applications in the Chemical Industry, Energy Development, and Environmental Protection

The book series appeals to a wide range of readers with backgrounds in physics, chemistry, biology, and medicine, from students at universities to scientists at institutes, in industrial companies and government agencies and ministries.

Ever since nanoscience was introduced many years ago, it has greatly changed our lives – and will continue to do so!

March 2016 Marcel Van de Voorde

About the Series Editor

Marcel Van de Voorde, Prof. Dr. ir. Ing. Dr. h.c., has 40 years' experience in European Research Organisations, including CERN-Geneva and the European Commission, with 10 years at the Max Planck Institute for Metals Research, Stuttgart. For many years, he was involved in research and research strategies, policy, and management, especially in European research institutions.

He has been a member of many Research Councils and Governing Boards of research institutions across Europe, the United States, and Japan. In addition to his Professorship at the University of Technology in Delft, the Netherlands, he holds multiple visiting professorships in Europe and worldwide. He holds a doctor honoris causa and various honorary professorships.

He is a senator of the European Academy for Sciences and Arts, Salzburg, and Fellow of the World Academy for Sciences. He is a member of the Science Council of the French Senate/National Assembly in Paris. He has also provided executive advisory services to presidents, ministers of science policy, rectors of Universities, and CEOs of technology institutions, for example, to the president and CEO of IMEC, Technology Centre in Leuven, Belgium. He is also a Fellow of various scientific societies. He has been honored by the Belgian King and European authorities, for example, he received an award for European merits in Luxemburg given by the former President of the European Commission. He is author of multiple scientific and technical publications and has coedited multiple books, especially in the field of nanoscience and nanotechnology.

Foreword

Nanophotonics is truly a multidisciplinary field of expertise. This immediately becomes clear from its definition as being the “study of the behavior of light on the nanometer scale, and of the interaction of nanometer-scale objects with light.” Consequently, nanophotonics involves both the science of light and the investigation of nanoscale structures and materials, especially the interaction between them. This new and prolific research area includes fields such as metamaterials, functional materials, and plasmonics.

The scientific breakthroughs, the application areas, and prospects of micro- and nanophotonics are remarkable as visualized in this book, covering the full spectrum from fundamental and applied research to industrial innovations. But what makes micro- and nanophotonics so exciting compared to photonics? The focus on submicrometer-scale effects provides a decisive differentiator in various ways. High-resolution metrology as in scanning near-field optical microscopy opens new characterization capabilities going below the light diffraction limit. In integrated nanophotonics, a large number of optical functions can be realized in a small area, making it a cost-effective and scalable platform as known from silicon semiconductor technology. Focusing light to nanometer-scale dimensions leads to high intensities facilitating nonlinear optical interactions that are otherwise not reachable. Furthermore, materials behave differently when they are shaped to nanometer-scale dimensions. Quantum mechanical effects as known, for example, from quantum dots or nanoparticles become now controllable, enabling light–matter interactions completely different from bulk materials.

Hence, micro- and nanophotonics enable new physics, novel applications, and scalability, making it a driver of innovation. The impact of photonics on our society is already immense and will keep increasing in the future. This has been nicely outlined by the International Year of Light and Light-based Technologies 2015 (IYL2015), endorsed by UNESCO. This successful global initiative has demonstrated to the world citizens the importance of light and optical technologies in everyday life and for the development of the society.

The purpose of this book is to present all novel aspects of nanophotonics and to help translate curiosity-driven research into the next-generation photonic devices and other innovative commercial products. The volume you are holding is a selection of 23 state-of-the art contributions with many links to databases and references, written by authors from all over Europe, the United States, and Asia. It is written for students of engineering sciences and physics, and will also be a great source of information and inspiration for professional scientists in research and industry. It is aimed to be a global reference for the photonics community, and hopefully will also find its way to policy makers and other stakeholders interested in finding solutions to the grand challenges of today.

We are convinced that you will enjoy reading this book and discovering the beauty and diversity of photonics at small length scales.

Principal Research Staff Member

Bert Jan Offrein

Head of Photonics, IBM Research – Zurich

President of the European Physical Society

Christophe Rossel

Emeritus RSM, IBM Research – Zurich

Preface

Photonics is now a worldwide acknowledged fundamental and applied topic recognized as a key enabling domain in which new tasks in the scientific and technological areas become possible. Generally, these tasks are accomplished in association with other technologies having in this way their potential enabled by micro- and nanophotonics.

As electronics lead to microelectronics, photonics lead to microphotonics and nanophotonics. For fundamental and practical reasons, micro- and nanophotonics, which were initially marginal in the optics and photonics domain, became the core of this domain. It can be said now that the essential of photonics is provided by micro- and nanophotonic outputs. Almost all the recent innovations involving photonics would have been impossible to achieve without the micro- and nanophotonics disruptive breakthroughs, enlarging in this way the action field of photonics.

The progresses in micro- and nanophotonics can be classified into two categories. The first one concerns “classical” optical instruments that have been downsized up to the microscale, the second one consists in implementing new functionalities by smart modulations of materials at the nanoscale that are out of reach of classical miniaturization approach, such as digital diffractive elements, integrated optics, and so on. This book covers these two categories. It is impossible nowadays to have a complete extended review of these both domains in one book. This book gives a smart overview of micro- and nanophotonics through some selected examples of applications with an analysis of their background. These applications have been selected for their representative interest. The prospective applications are so varied that only some strong examples were taken into account

In the future, a new nano and micro industry incorporating photonics will take shape allowing a chance for Europe to catch up with the manufacturing of micro- and nanophotonics devices including production because it can be done with the almost exclusive use of robotics under digital control.

We have tried to feature in this book some of the enabling essentials of micro- and nanotechnologies considered more from the point of view of the engineer than from the point of view of the pure scientist. We have considered what can be helpful for a satisfying running and more of the many micro- and nanophotonics devices as micro- and nanosensors that will be found in our immediate surroundings (cars and planes, for instance)

This book will pave the way for general physicists, engineers, and technician to enter the field of nanophotonics. In addition, the book will also be a good reference for undergraduate, graduate, and postgraduate students from almost all the technical and biotechnical disciplines. We hope that this book will be valuable also for experts in the field as a good tool to identify where some key progress is occurring that is not in their field of view.

The world is becoming more and more digital. This is also the case in micro- and nanophotonics. All the micro- and nanophotonics introduced in this book exist as digital models, more or less complete, which were used as a basis for their hardware versions. The digital conception methods are following the progress of physics concepts.

In this book are introduced micro- and nanophotonic devices at different levels of development: some of them are at the basic concept level, some others have been tested for fulfilling challenging applications needs, and some of them are at the digital intermediary level.

The applications considered in this book are in a large range showing the versatility and the strong enabling potential of micro- and nanophotonics. It can thus be noticed that in the chapters of this book micro- and nanophotonics is associated with chemistry, telecom, media, space, physics, computer sciences, biomedical systems, clean energy, and so on.

The ability to enter all these fields is very stimulating for students who are taking, when this is possible, a major in photonics when they realize that photonics is, in fact, opening for them pluridisciplinary and evolutive careers. It seems reasonable to consider that we are witnessing only the blossoming of micro- and nanophotonics that will accelerate in the coming years. The year of light is a milestone in this trend.

Education is very important for the future of micro- and nanophotonics. Most of the chapters in this book impart advanced education in micro- and nanophotonics. This is why pedagogy is so significant in a majority of chapters. It is necessary to increase the number of well-trained engineers, scientists, and technicians to assume the many forecast innovations in micro- and nanophotonics. The areas of the world where they will take place will be the ones where the dedicated high-level workforce will be in place.

The growing interest in micro- and nanophotonics is shown by the fast growing numbers of attendees to the photonics conferences incorporating in large part micro- and nanophotonics. Many of these attendees are newcomers to micro- and nanophotonics drawn to these conferences by the disruptive intrusion of micro- and nanophotonics in their work domain. This book will also help them structure their concerns with regard to micro- and nanophotonics.

July 2016

Patrick Meyrueis University of Strasbourg, France

Marcel Van de VoordeUniversity of Technology Delft,The Netherlands

An Overview of Micro- and Nanophotonic Science and Technology

David L. Andrews

University of East Anglia, School of Chemistry, Norwich Research Park, Norwich NR4 7TJ, UK

1 Global Scale of the Subject

The widely ranging subject of micro- and nanophotonics represents a spectrum of one of the most exciting, rapidly progressing areas of modern science and technology. It has the unusual distinction of exhibiting rapid, almost neck and neck pace in the developments of both its fundamental scientific basis, and in market-ready applications, where sustained progress in the miniaturization and integration of optical components has already led micro- and nanophotonic technologies into a remarkably prominent position in the commercial market. As miniature lasers and microfabrication methods have continually evolved, parallel growth in the optical fiber industry has helped spur the continued push towards the long-sought goal of total integration in optical devices.

This is a sector in which further, much more rapid commercialization can be expected to take place over the next decade and beyond. There is already a much more widely dawning recognition of the true significance of this field: it has become a global phenomenon, as indeed befits its widely-vaunted promise for tangible societal impact. Although it is hard to draw the line and obtain broken-down figures for the micro- and nanophotonic technologies per se, it is realistic to suppose that they already account for a significant fraction of a worldwide photonics enterprise that generates over 500 billion dollars of annual trade, and which accounts for employment figures of around 2.3 million individuals (2015 figures, data from SPIE) [1].

It has often been remarked that the present century will become – if it is not already – one in which light and photonics will supplant electricity and electronics as the pre-eminent influences transforming modern society. Indeed this is entirely fitting; it seems that the term “photonics” was originally coined with just such a vision in mind [2]. So, whilst scientific advances still race on in fields including quantum optics, cavity photonics, nonlinear optics, plasmonics and metamaterials, we can identify applications already heading into market in the form of solid-state lighting and displays, optical interconnect technology, electronic chips and physical platforms for quantum computing, materials for solar energy capture, methodologies for bio-imaging, surface processing, optical manipulation, and many more.

At the heart of all this activity are physical systems that can exploit forms of optical interaction whose nature is substantially modified – and in some cases almost entirely determined – by microscopic and nanoscale features. Over these length scales the whole character of optical propagation, transmission and measurement will often involve an intricate interplay of structural, spectroscopic, electromagnetic, electronic, and ultimately quantum optical features. In fact, a great deal of the subject matter that nowadays features under the generic heading “photonics” is directly associated with technologies of micro- or nano-scale dimensions, whose growth in importance links with the inexorable drive to greater and greater miniaturization. A case can be made that this is what most clearly distinguishes photonics in general from the rest of modern optics: the realm of electromagnetic phenomena over micro- and nanoscale dimensions is a realm within which optics often needs to be described in terms of photon (or plasmon/polariton) interactions. We shall return to look more closely at characteristics of the physics in Section 3.

A broad range of technological advances enables new opportunities to be recognized and exploited. In this highly interdisciplinary field, two main forms of materials innovation drive forward the research and development. In advanced chemistry laboratories, “bottom-up” innovations in chemical synthesis enable the production of new kinds of “supramolecular” material [3]. Here, as one moves up the scale beyond molecular dimensions (typically no more than a few nanometres) the optical and electronic properties of the product materials can be wholly different from the substances of which they are formed. Even the simplest examples, such as graphene and the fullerenes, dramatically illustrate the significance of size and morphology in determining physical properties. In other materials, a capacity for self-assembly represents an attractive means of scaling up for commercially appropriate levels of production. Meanwhile, “top-down” advances in materials processing, usually achieved through computer-controlled sub-micron lithography in purpose-built clean-room facilities, enable high powered laser and electron beam methods to sculpt and process wafers and surfaces [4]. The largest impact is in laser lithography, which is now producing features of 10 nm resolution on silicon wafers. Moreover, the use of lasers enables wafer bonding, with interface regions as little as 2 nm across. These advances have opened up a much wider scope for the production of multilayer photonic devices such as high efficiency photovoltaic cells.

2 A Brief History

A comprehensive history of this subject is well beyond the scope of this article – yet, though it is an invidious task to make a selection, it is appropriate to highlight a few of the numerous milestones that mark and typify the fascinating progress in this field over the years. At the outset it is worth emphasizing that a considerable number of achievements reported under the “nano” banner in recent times might – depending on definition – have been more precisely termed “microscale”: in some areas, the achievement of truly nanoscale (sub-micron) operation remains a tantalizing goal. Nonetheless, the convenient cover-all term “nanophotonics” has gained increasing prominence since the field of nanotechnology itself acquired a long-sought respectability in the early years of this century. By then, the originally revolutionary sound of the term “nanotechnology” had finally outgrown the hype and the negative connotations with which reports of the earliest “nano” topics were often burdened. Broadly speaking, the more specific field of nanophotonics is itself a subject area that can also be regarded as almost synonymous with “nano-optics” – though the latter term is perhaps slightly more often used for instrumentation rather than phenomena; for example, nano-optics the designation more commonly understood to include topics such as near-field microscopy.

It is also worth tracing back the evolution of “photonics” itself. This broad term, originally introduced to the technical community by the rocket engineer Sänger [2], first came into real prominence in 1982, when the trade publication that had previously been entitled Optical Spectra changed its name to Photonics Spectra. At that time the new term, like “nanotechnology,” also had an exotic and somewhat contrived ring to it, but with increasing usage it soon became associated with numerous technical advances. By coincidence, for example, this was the year in which the first audio CD was released – an event that quickly launched the mass market for microscale laser technology. And just five years later, Tang and Van Slyke were to report operation of the first OLED (an organic light-emitting diode) device [5], paving the way for an increasingly competitive technology that would eventually come into its own with the development of smart phones and tablets. At much the same time, the advent of “quantum dots” (QD) [6], not at first overtly linked to the subject of photonics, soon became almost emblematic of photonic technology, the forerunner of a host of material structures whose optical parameters could be designed and determined just as much by physical dimensions as by chemical composition. The term “photonics” began to acquire a much firmer acceptance in academic circles with the publication in 1991 of Saleh and Teich's definitive treatise on its scientific foundations [7].

The following year, the discovery by Allen et al. [8] that suitably wavefront-structured light could convey orbital angular momentum – beyond the well-known spin associated with circular polarizations – paved the way for the spectacular growth of a new field now generally known as “complex” (or structured) light, closely associated with singular optics [9]. This is a field that has opened up a host of new avenues for research and applications, to the extent that in a typical year several dedicated meetings around the globe regularly supplement an annual conference on this topic at the major convention Photonics West. The attraction here is not only the fascination of entirely new principles; it is also the fact that application potential has been identified in a host of different arenas [10]. Another notable advance, in the years running up to the millennium, was the achievement by Ebbesen et al. [11], of extraordinarily strong optical transmission through sub-wavelength apertures. Once again, local structure above the atomic level was being observed to generate a distinctive optical response, entirely different from what would be expected on the simple basis of physical scaling.

In recognition of the capacity to precision engineer new materials on sub-wavelength scales, the pursuit of theory and allied experimentation has further revealed that entirely new kinds of optical phenomenon such as the astonishing phenomena of negative refraction [12] and optical cloaking [13] could occur. As with many other previous advances in optics – the early history of the laser itself being a prime example – initial successes at long wavelengths well beyond the visible range have encouraged strenuous efforts to move towards higher optical frequencies, where a range of imaginative applications are already envisaged. The current rate of growth in such areas surpasses much else in modern optics, little more than ten years after these methods first gained serious attention. Across the subject as a whole, the most important innovations are always underpinned by continuing progress in theory and computational modeling.

With this rich provenance and accelerating pace of advances, it is perhaps surprising to reflect back that it was only at the turn of the present century that the composite term “nanophotonics” began to emerge in its own right. Certainly it was at this juncture that the scale of interest in such topics, and a recognition of their significance, began to attract major players in the scientific journal and conference trade. The first major journal to be launched specifically to cater for the subject – Elsevier's Photonics and Nanostructures – Fundamentals and Applications, began publication in 2003. The same year was marked by the founding of the European Photonics Industry Consortium and a landmark in the following year was the publication by Prasad of the first book specifically entitled Nanophotonics [14]. Two years later the first major international conference on this topic was staged by SPIE (the international society for optics and photonics) in Strasbourg, France. The first serial publication with the exact term in its title, the Journal of Nanophotonics, was launched by the same organization the next year, as was a definitive textbook, Novotny and Hecht's Principles of Nano-Optics [15].

Over the first decade of the new millennium, nanophotonics came to represent not just a combination of established nanoscience and photonics regimes; the union produced a spectacular progeny of sub-topics, especially in connection with surface plasmonics and metamaterials, where further entirely new kinds of optical phenomenon have been identified. The former represents a field that has suddenly matured and expanded, based on a long-held realization that light directed along a metal surface can lead to an unusually strong engagement with conduction band electrons. In the more detailed understanding that has now emerged, it is recognized that the strength of this coupling effectively essentially blurs the distinction between photons and electronic excitation propagating along the surface. This, it is possible to achieve electric field strengths many orders of magnitude higher than one would expect from light alone [16]. The more generic field of metamaterials, on the other hand, exploits the rich variety of dielectric and magnetic properties that can be produced in material structures that are built from micron or sub-micron sized components, layers, and channels.

In the years leading up to the present day, the year 2007 represents a notable landmark for the launch of Apple's iPhone – followed just three years later by the iPad – both of them devices whose components are substantially based on microphotonic elements and fabrication methods. Another notable industry event was Sony's launch in 2013 of their Triluminous HDTV, the first quantum dot–based consumer display. The same year saw the inauguration in the United States of The National Photonics Initiative (NPI) – an alliance aiming to advance the broad cause of photonics research and development, primarily argued on the basis of growing the US economy and improving national security. In Europe, the same notable year also saw publication of a strategic roadmap for the photonics industry [17]. And the momentum has continued to grow – not just in the States but in other major competing economies, most recently spurred on by the highly successful United Nations International Year of Light and Light-Based Technologies [18]. And so it is that, at the present juncture, the successes of micro- and nanoscale photonics are cutting an increasingly broad swathe across the landscape of both industrial and consumer technology.

3 Characteristics

It is a thought-provoking challenge to attempt identifying what truly characterizes the plethora of topics that are now covered by the umbrella term “micro- and nanophotonics.” Often, the involvement of such features is not readily apparent in the applications themselves, which can involve a rich variety of structures and materials [19]: in some market-ready appliances, the fact that micro-engineering technologies facilitate the achievement of improved operational specifications is really of little concern to the end user. By the use of cleverly tailored optical fiber, for example, an improvement of higher data transfer rates, or reduction of energy costs, are perfectly legitimate goals in their own right. In this sector, the fact that such objectives can be achieved by microtechnology primarily represents an expedient means to that end. However, for some other technologies, the utilization of micro- or nanoscale mechanisms does have a more direct bearing on use, as for example with optical methods of cell separation, or super-resolution microscopy. Nonetheless, among the wide range of applications, it is possible to identify some common ground in the types of fundamental property and phenomenon that are most often involved.

In general, it is the characteristics of optical propagation, localization, and dispersion (in the sense of variation with optical frequency or wavelength) that most often play the crucial role, for in sufficiently small regions each of these can display behavior that is completely different to bulk media, and that would indeed be regarded as anomalous if they occurred on that scale. A great deal of the active research in this area either directly or indirectly concerns surfaces – for example nanofabricated surfaces and surface plasmonics, thin film optics, near-field interactions, evanescent waves and sub-wavelength aperture effects. Other kinds of optical action are revealed by supramolecular and polymeric systems, cavity nanophotonic structures and nano-antennas. It is instructive to identify some of the main principles, and we can begin by considering issues associated with the propagation of light over nanoscale dimensions.

3.1 Propagation

To set the proper context it has to be borne in mind that, with the exception of effects such as reflection, specifically associated with surfaces (where a variety of features such as roughness play a part), the optical properties of most bulk, homogeneous media are to a very large extent determined by the electromagnetic properties of the constituent atoms or molecules – making due allowance for the emergence of band structures in semiconductors and metals. So, while optical character is commonly recorded in terms of a wavelength-dependent refractive index – comprising both a real and an imaginary part to account for both refraction and attenuation – the celebrated Clausius-Mossotti relation provides a straightforward link to electronic polarizability at the atomic or molecular level. The polarizability, in turn, is expressible in terms of quantum mechanical properties associated with absorption profiles [20]. In consequence, the bulk character is ultimately determined by chemical constitution, alone.

However the situation changes dramatically when we introduce confined spaces over wavelength or sub-wavelength scales. Although often overlooked, one of the first and most obvious reasons why the linkage of properties across the dimensional scales summarized above ceases to be effective, is because an assumed three-dimensionality is compromised. For this reason the somewhat awkward descriptors “zero-dimensional,” “one-dimensional” and “two-dimensional” have gained currency to respectively designate nanoparticles, nanorods (also nanowires) and thin films: in each case the stated “dimensionality” signifies the extent to which the structure repeats itself, or at least ceases to impose significant boundary conditions [21]. A simple glance at the Clausius-Mossotti equation tells us that it will be inapplicable because it deals only with scalar quantities, that is, parameters that have the same value irrespective of direction. Many single-component materials intrinsically lack such symmetry, exhibiting uniaxial or biaxial refraction for example. But on the nanoscale, the imposition of tightly confining boundaries will often exert a far greater effect than simply to differentiate the optical properties associated with a corresponding dimension. Boundary conditions can moderate the form of electronic wavefunctions, and thereby often exert an influence that dominates the optical behavior – as can be strikingly exhibited by the variation in color of fluorescence from quantum dots of identical composition but different size [22]. This illustrates the additional complexity – and opportunity for creative materials design – when atomic or molecular constitution no longer adequately accounts for optical response. We shall return to dispersion issues shortly.

We then have to consider aspects of propagation at surfaces and interfaces. The fabrication of tailor-made surface structures offers opportunities to deliver many kinds of optical phenomenon specifically associated with specular reflection and diffraction, and since lithography advanced into the nanoscale regime a variety of new possibilities have emerged. Direct surface nano-patterning has become available as a large-scale operation through parallel processing using two-dimensional arrays, based on the transformative technology of dip-pen nanolithography [23]. It has been shown how new degrees of freedom can be attained by introducing abrupt phase changes over the scale of an optical wavelength, requiring a rewrite of the traditional laws of reflection and refraction [24]. By building nanostructures onto a suitable substrate, sculptured thin films can be engineered to produce highly polarization-selective characteristics – including, in the case of chiral structures, a remarkable differentiation between circular polarizations [25].

In dealing more generally with the highly distinctive form of electromagnetic waves that can propagate at boundaries, a still richer variety of possibilities is found to arise. Here, a distinction can be made between propagation across and along boundaries; the rich field of surface plasmonics is primarily associated with the latter [26]. For dielectric materials, too, simply identifying the increasing polariton behavior as the optical frequency approaches a resonance again tells only part of the story; at interfaces a whole catalog of different kinds of guided wave can be identified [27]. In the science of multi-core optical fibres and waveguides it is crucially important to understand and correctly model the characteristics and dynamics of propagation, especially in developing the technology of fiber lasers and amplifiers where there is also active photonics involved [28]. One type of optical fiber known as a photonic crystal fiber (PCF) takes advantage of stopband dispersion to achieve high-fidelity confinement by exploiting this principle, and in consequence delivers extremely low, very significantly sub-decibel losses per kilometer [29].

Meanwhile there are other challenges to address in connection with focusing and imaging in turbid media. This requires novel means of dealing with the propagation of optical signals through largely disordered, often absorptive and/or chemically heterogeneous media – such as biological tissue. With early successes exploiting optical coherence [30] leading on to newer methods to achieve focusing through spatial light modulator (SLM) wavefront-shaping [31], recent advances have now shown that it is even possible to image within turbid media by the analysis of incoherent scattered light, by using probe radiation with a suitably shaped wavefront [32]. Refining the technique and solving the associated issues is of major importance in several fields of medicine ranging from surgical ablation and scission procedures, through photodynamic therapy to non-invasive sensing [33]. Such considerations naturally lead us to reflect next on broader aspects of optical localization and imaging.

3.2 Localization

It is well known that the instrumentation of classical optics is fundamentally limited by Abbe's diffraction limit, connected to the essential wave nature of light. At the photon level, frustrations of a similar kind arise due to quantum uncertainty. In both respects, there is a difficulty in securing, with high fidelity, information that is localized to less than about a wavelength. Nonetheless, for a host of reasons (including the use of optical elements made of glass or optical quality polymer, and also the relative safety for human activities) operation within the visible range is almost always to be preferred – and this would normally be considered to impose severe limits on the extent of sub-micron scale applications.

A major breakthrough in tackling this problem came in 1999, with a report of achieving sub-diffraction resolution in far-field fluorescence microscopy. One of authors (Hell) went on to be awarded the 2014 Nobel Prize in Chemistry for its development, and success in breaking the Abbe limit. The method, which involves a spatially selective de-excitation of initially excited molecules through stimulated emission by a secondary beam, has become known as stimulated emission depletion (STED) [34]. Another route to enhanced image resolution is through illumination with wavefront structures in the form of “light sheets” [35]. Meanwhile, the STED mechanism has also been proposed as a means of finessing the resolution of 3D printing into the nanoscale regime [36].

Another insight into the issues of localization and precision imaging is neatly encapsulated in some remarks from Ohtsu, another pioneer of nanophotonics: “if a sub-wavelength-sized nanometric similar particle is used to absorb light, it works as a photodetector, and consequently, the photon can be detected and its position determined by the size of the particles with high spatial accuracy. This means that a local interaction between nanometric particles and photons is required to go beyond the diffraction limit. Furthermore, the energy transferred via this interaction must be dissipated in the nanometric particles or adjacent macroscopic particles to fix the position and magnitude of the transferred energy” [37].

Indeed, the near-field transfer of energy in the form of electronic excitation (resonance energy transfer: RET) is one of the most effective ways of achieving localization: [38] in the living world, it is a mechanism to be found at the heart of photosynthetic systems, where the energy of several photons has to be collected together to generate sufficient redox potential for the necessary electron transfer processes to commence. The same mechanism is now harnessed in the technology of numerous other systems including fluorescence-based nanosensors [39], and a recognition of the fundamental quantum basis for this kind of effect has required new formulations of theory [40]. A range of more exotic, multiphoton phenomena is also being developed to deploy RET in rare-earth doped materials [41] as a means of achieving optical frequency up- and down-conversion [42]. Much of the interest here centers on energy harvesting – for the more effective utilization of solar wavelengths beyond the visible range – and in solid-state lighting, for producing hues that can be used in tailored combinations to emulate sunlight or generate mood.

There is another important aspect of localization: the capacity of focused laser light to trap and manipulate small particles of matter. Optical forces on matter often require light fields with specially formed structural features. Although the most straightforward optical tweezer methods are based on simple intensity differentials, usually near a focus, there are beams with vortices or other kinds of phase structure – hollow beams, tailor-made optical traps, sheets of light, and evanescent waves for example – which offer additional opportunities for ultra-fine control. Through the exchange of linear or angular momentum between light and matter, force fields and torques can be produced whose variation over nanoscale dimensions have no counterpart in conventional optical beams [10].

In this area, most of the work that has translated to real-world applications thus far achieves the control of micron-sized particles in suspension using “optical tweezers” forces, leading to a host of uses for optical sorting and medical screening, for example [43]. Again, by the use of micron-scale tools, fabricated to design by computer-guided two-photon polymerization, it is possible to achieve exquisite control over the position and orientation of nanoscale particles in suspension [44]. Furthermore, there is an additional kind of optomechanical interaction that operates only over micro- and nanoscale distances – a form of non-contact coupling between optically trapped particles known as “optical binding” [45]. It proves capable of holding sub-wavelength scale particles in loose, but stable assemblies held together by the force of light alone – in a way that superficially resembles the stable agglomeration of atoms in the form of molecules, by electrical force [46].

Other innovations make it possible to achieve simultaneous active control over more particles, by taking advantage of non-uniform light beams, structured over dimensions comparable to their wavelength. The associated optical engineering can take the form of wavefront structuring as referred to earlier – an exotic example being the use of Airy beams to steer microparticles into microwell traps [47] – or through beam configurations such as optical lattices, holographic optical traps, or parallel filament structures programmed into a spatial light modulator (SLM). For the trapping of much smaller species, thermal disturbance tends to become increasingly problematic, and at the atomic level extreme cooling is necessary; the twin requirements of optical cooling and trapping are often achieved with laser and vacuum technology. Despite experimental setups that are much more expensive and demanding than bench-top laser tweezers, researchers are drawn by the exotic properties of cold atom ensembles, which offer wide-ranging possibilities for the storage of quantum information [48]. Structured light is also of considerable interest for its intrinsic capacity to convey a higher density of information than traditional laser beams [49]. Directly harnessing its orbital angular momentum affords a host of new methods for guiding the motion of particles, and potential applications already include liquid microviscometry [50]. This is once again an area in which the spatial light modulators find application, as a means of generating programmable vortex beam structures [51].