1、OXFORD MASTER SERIES IN PHYSICSOXFORD MASTER SERIES IN PHYSICSThe Oxford Master Series is designed for final year undergraduate and beginning graduate students in physicsand related disciplines. It has been driven by a perceived gap in the literature today. While basic undergraduatephysics texts oft
2、en show little or no connection with the huge explosion of research over the last two decades,more advanced and specialized texts tend to be rather daunting for students. In this series, all topics and theirconsequences are treated at a simple level, while pointers to recent developments are provide
3、d at various stages.The emphasis is on clear physical principles like symmetry, quantum mechanics, and electromagnetism whichunderlie the whole of physics. At the same time, the subjects are related to real measurements and to theexperimental techniques and devices currently used by physicists in ac
4、ademe and industry. Books in this seriesare written as course books, and include ample tutorial material, examples, illustrations, revision points, andproblem sets. They can likewise be used as preparation for students starting a doctorate in physics and relatedfields, or for recent graduates starti
5、ng research in one of these fields in industry.CONDENSED MATTER PHYSICS1. M. T. Dove: Structure and dynamics: an atomic view of materials2. J. Singleton: Baud theory and electronic properties of solids3. A. M. Fox: Optical properties of solids4. S. J. Blundell: Magnetism in condensed matter5. J. F.
6、Annett: Superconductivity6. R. A. L. Jones: Soft condensed matterATOMIC, OPTICAL, AND LASER PHYSICS7. C. J. Foot: Atomic Physics8. G. A. Brooker: Modern classical optics9. S. M. Hooker, C. E. Webb: Laser physics15. A. M. Fox: Quantum optics: an introductionPARTICLE PHYSICS, ASTROPHYSICS, AND COSMOLO
7、GY10. D. H. Perkins: Particle astrophysics11. Ta-Pei Cheng: Relativity, gravitation, and cosmologySTATISTICAL, COMPUTATIONAL, AND THEORETICAL PHYSICS12. M. Maggiore: A modern introduction to quantum field theory13. W. Krauth: Statistical mechanics: algorithms and computations14. J. P. Sethna: Entrop
8、y, order parameters, and complexityQuantum OpticsAn IntroductionMARK FOXDepartment of Physics and AstronomyUniversity of Sheeld13Great Clarendon Street, Oxford OX2 6DPOxford University Press is a department of the University of Oxford.It furthers the Universitys objective of excellence in research,
9、scholarship,and education by publishing worldwide inOxford New YorkAuckland Cape Town Dar es Salaam Hong Kong KarachiKuala Lumpur Madrid Melbourne Mexico City NairobiNew Delhi Shanghai Taipei TorontoWith oces inArgentina Austria Brazil Chile Czech Republic France GreeceGuatemala Hungary Italy Japan
10、Poland Portugal SingaporeSouth Korea Switzerland Thailand Turkey Ukraine VietnamOxford is a registered trade mark of Oxford University Pressin the UK and in certain other countriesPublished in the United Statesby Oxford University Press Inc., New Yorkc Oxford University Press 2006The moral rights of
11、 the author have been assertedDatabase right Oxford University Press (maker)First published 2006All rights reserved. No part of this publication may be reproduced,stored in a retrieval system, or transmitted, in any form or by any means,without the prior permission in writing of Oxford University Pr
12、ess,or as expressly permitted by law, or under terms agreed with the appropriatereprographics rights organization. Enquiries concerning reproductionoutside the scope of the above should be sent to the Rights Department,Oxford University Press, at the address aboveYou must not circulate this book in
13、any other binding or coverand you must impose the same condition on any acquirerBritish Library Cataloguing in Publication DataData availableLibrary of Congress Cataloging in Publication DataFox, Mark (Anthony Mark)Quantum optics : an introduction/Mark Fox.p. cm. (Oxford master series in physics ; 6
14、)Includes bibliographical references and index.ISBN-13: 9780198566724 (hbk. : acid-free paper)ISBN-10: 0198566727 (hbk. : acid-free paper)ISBN-13: 9780198566731 (pbk. : acid-free paper)ISBN-10: 0198566735 (pbk. : acid-free paper)1. Quantum optics. I. Title. II. Series.QC446.2.F69 2006535prime.15dc22
15、 2005025707Typeset by Newgen Imaging Systems (P) Ltd., Chennai, IndiaPrinted in Great Britainon acid-free paper byAntony Rowe, ChippenhamISBN 0198566727 9780198566724ISBN 0198566735 (Pbk.) 9780198566731 (Pbk.)10987654321PrefaceQuantum optics is a subject that has come to the fore over the last 1020y
16、ears. Formerly, it was regarded as a highly specialized discipline, acces-sible only to a small number of advanced students at selected universities.Nowadays, however, the demand for the subject is much broader, withthe interest strongly fuelled by the prospect of using quantum optics inquantum info
17、rmation processing applications.My own interest in quantum optics goes back to 1987, when I attendedthe Conference on Lasers and Electro-Optics (CLEO) for the firsttime. The ground-breaking experiments on squeezed light had recentlybeen completed, and I was able to hear invited talks from the lead-i
18、ng researchers working in the field. At the end of the conference, Ifound myself suciently interested in the subject that I bought a copyof Loudons Quantum theory of light and started to work through it ina fairly systematic way. Nearly 20 years on, I still consider Loudonsbook as my favourite on th
19、e subject, although there are now many moreavailable to choose from. So why write another?The answer to this question became clearer to me when I tried todevelop a course on quantum optics as a submodule of a larger unitentitled Aspects of Modern Physics. This course is taken by under-graduate stude
20、nts in their final semester, and aims to introduce them toa number of current research topics. I set about designing a course tocover a few basic ideas about photon statistics, quantum cryptography,and BoseEinstein condensation, hoping that I would find a suitable textto recommend. However, a quick
21、inspection of the quantum optics textsthat were available led me to conclude that they were generally pitchedat a higher level than my target audience. Furthermore, the majoritywere rather mathematical in their presentation. I therefore reluctantlyconcluded that I would have to write the book I was
22、seeking myself. Theend result is what you see before you. My hope is that it will serve bothas a useful basic introduction to the subject, and also as a tasty horsdoeuvre for the more advanced texts like Loudons.In developing my course notes into a full-length book, the first prob-lem that I encount
23、ered was the selection of topics. Traditional quantumoptics books like Loudons assume that the subject refers primarily tothe properties of light itself. At the same time, it is apparent that thesubject has broadened considerably in its scope, at least to many peopleworking in the field. I have ther
24、efore included a broad range of topicsthat probably would not have found their way into a quantum opticstext 20 years ago. It is probable that someone else writing a similar textvi Prefacewould make a dierent selection of topics. My selection has been basedmainly on my perception of the key subject
25、areas, but it also reflects myown research interests to some extent. For this reason, there are proba-bly more examples of quantum optical eects in solid state systems thanmight normally have been expected.Some of the subjects that I have selected for inclusion are still develop-ing very rapidly at
26、the time of writing. This is especially true of the topicsin quantum information technology covered in Part IV. Any attempt togive a detailed overview of the present status of the experiments in thesefields would be relatively pointless, as it would date very quickly. I havetherefore adopted the str
27、ategy of trying to explain the basic principlesand then illustrating them with a few recent results. It is my hope thatthe chapters I have written will be sucient to allow students who arenew to the subjects to understand the fundamental concepts, therebyallowing them to go to the research literatur
28、e should they wish to pursueany topics in more detail.At one stage I thought about including references to a good number ofinternet sites within the Further Reading sections, but as the links tothese sites frequently change, I have actually only included a few. I amsure that the modern computer-lite
29、rate student will be able to find thesesites far more easily than I can, and I leave this part of the task to thestudents initiative. It is a fortunate coincidence that the book is goingto press in 2005, the centenary of Einsteins work on the photoelectriceect, when there are many articles available
30、 to arouse the interest ofstudents on this subject. Furthermore, the award of the 2005 NobelPrize for Physics to Roy Glauber “for his contribution to the quantumtheory of optical coherence” has generated many more widely-accessibleinformation resources.An issue that arose after receiving reviews of
31、my original book planwas the diculty in making the subject accessible without gross over-simplification of the essential physics. As a consequence of these reviews,I suspect that some sections of the book are pitched at a slightly higherlevel than my original target of a final-year undergraduate, an
32、d wouldin fact be more suitable for use in the first year of a Masters course.Despite this, I have still tried to keep the mathematics to a minimum asfar as possible, and concentrated on explanations based on the physicalunderstanding of the experiments that have been performed.I would like to thank
33、 a number of people who have helped in the var-ious stages of the preparation of this book. First, I would like to thankall of the anonymous reviewers who made many helpful suggestions andpointed out numerous errors in the early versions of the manuscript.Second, I would like to thank several people
34、 for critical reading ofparts of the manuscript, especially Dr Brendon Lovett for Chapter 13,and Dr Gerald Buller and Robert Collins for Chapter 12. I would liketo thank Dr Ed Daw for clarifying my understanding of gravity waveinterferometers. A special word of thanks goes to Dr Geo Brooker forcriti
35、cal reading of the whole manuscript. Third, I would like to thankSonke Adlung at Oxford University Press for his support and patiencePreface viithroughout the project and Anita Petrie for overseeing the productionof the book. I am also grateful to Dr Mark Hopkinson for the TEM pic-ture in Fig. D.3,
36、and to Dr Robert Taylor for Fig. 4.7. Finally, I wouldlike to thank my doctoral supervisor, Prof. John Ryan, for originallypointing me towards quantum optics, and my numerous colleagues whohave helped me to carry out a number of quantum optics experimentsduring my career.SheeldJune 2005This page int
37、entionally left blank ContentsList of symbols xvList of abbreviations xviiiI Introduction and background 11 Introduction 31.1 What is quantum optics? 31.2 A brief history of quantum optics 41.3 How to use this book 62 Classical optics 82.1 Maxwells equations and electromagnetic waves 82.1.1 Electrom
38、agnetic fields 82.1.2 Maxwells equations 102.1.3 Electromagnetic waves 102.1.4 Polarization 122.2 Diraction and interference 132.2.1 Diraction 132.2.2 Interference 152.3 Coherence 162.4 Nonlinear optics 192.4.1 The nonlinear susceptibility 192.4.2 Second-order nonlinear phenomena 202.4.3 Phase match
39、ing 233 Quantum mechanics 263.1 Formalism of quantum mechanics 263.1.1 The Schrodinger equation 263.1.2 Properties of wave functions 283.1.3 Measurements and expectation values 303.1.4 Commutators and the uncertainty principle 313.1.5 Angular momentum 323.1.6 Dirac notation 343.2 Quantized states in atoms 353.2.1 The gross structure 353.2.2 Fine and hyperfine structure 393.2.3 The Zeeman eect 413.3 The harmonic oscillator 413.4 The SternGerlach experiment 433.5 The band theory of solids 45
