OPTICAL COATINGS AND THERMAL NOISE IN PRECISION MEASUREMENT pot

OPTICAL COATINGS AND THERMAL NOISE IN PRECISION MEASUREMENT Thermal noise from optical coatings is a growing area of concern, and overcoming limits to the sensitivity of high-precision measurements by thermal noise is one of the greatest challenges faced by experimental physicists. In this timely book, internationally renowned scientists and engineers examine our current theoretical and experimental understanding. Beginning with the theory of thermal noise in mirrors and substrates, subsequent chapters discuss the technology of depositing coatings and state-of-the-art dielectric coating techniques used in precision measurement. Applications and remedies for noise reduction are also covered. Individual chapters are dedicated to specific fields where coating thermal noise is a particular concern, including the areas of quantum optics/optomechanics, gravitational wave detection, precision timing, high-precision laser stabilization via optical cavities, and cavity quantum electrodynamics. While providing full mathematical detail, the text avoids field-specific jargon, making it a valuable resource for readers with varied backgrounds in modern optics. Gregory Harry has worked in the field of gravitational wave detection for over 15 years and is currently the Optics Chair and Coating Cognizant Scientist for the Laser Inter- ferometer Gravitational Wave Observatory (LIGO), and Professor at American University, Washington DC. He is amongst the pioneers of coating thermal noise research. Timothy P. Bodiya is a graduate student at the Physics Department of Massachusetts Institute of Technology. He is conducting research in the field of gravitational wave physics and quantum optomechanics with the goal of measuring quantum effects on everyday-sized objects (gram to kilogram size). Riccardo DeSalvo is Professor at the University of Sannio in Benevento, Italy. Previously he has held the positions of Senior Staff Scientist at LIGO, Caltech, Passadena, and that of Staff Scientist at INFN in Pisa, Italy. He is a member of ASME, APS, and SIF and has authored more than 200 refereed papers. OPTICAL COATINGS AND THERMAL NOISE IN PRECISION MEASUREMENT Edited by GREGORY HARRY American University, Washington DC TIMOTHY P. BODIYA Massachusetts Institute of Technology and RICCARDO DESALVO Universit ´ a degli Studi del Sannio, Benevento, Italy cambridge university press Cambridge, New York, Melbourne, Madrid, Cape Town, Singapore, S ˜ ao Paulo, Delhi, Tokyo, Mexico City Cambridge University Press The Edinburgh Building, Cambridge CB2 8RU, UK Published in the United States of America by Cambridge University Press, New York www.cambridge.org Information on this title: www.cambridge.org/9781107003385 C  Cambridge University Press 2012 This publication is in copyright. Subject to statutory exception and to the provisions of relevant collective licensing agreements, no reproduction of any part may take place without the written permission of Cambridge University Press. First published 2012 Printed in the United Kingdom at the University Press, Cambridge A catalogue record for this publication is available from the British Library Library of Congress Cataloging in Publication data Optical coatings and thermal noise in precision measurement / edited by Gregory M. Harry, Timothy Bodiya and Riccardo DeSalvo. p. cm. Includes bibliographical references. ISBN 978-1-107-00338-5 (hardback) 1. Optical coatings. 2. Quantum optics. 3. Light – Scattering. 4. Electromagnetic waves – Scattering. I. Harry, Gregory M., 1967– II. Bodiya, Timothy P. III. DeSalvo, Riccardo. TS517.2.O64 2012 621.36 – dc23 2011039977 ISBN 978-1-107-00338-5 Hardback Cambridge University Press has no responsibility for the persistence or accuracy of URLs for external or third-party internet websites referred to in this publication, and does not guarantee that any content on such websites is, or will remain, accurate or appropriate. Contents List of contributors page vii Foreword xi Preface xiii 1 Theory of thermal noise in optical mirrors 1 y. levin 2 Coating technology 6 s. chao 3 Compendium of thermal noises in optical mirrors 20 v. b. braginsky, m. l. gorodetsky, and s. p. vyatchanin 4 Coating thermal noise 31 i. martin and s. reid 5 Direct measurements of coating thermal noise 55 k. numata 6 Methods of improving thermal noise 73 s. ballmer and k. somiya 7 Substrate thermal noise 93 s. rowan and i. martin 8 Cryogenics 108 k. numata and k. yamamoto 9 Thermo-optic noise 129 m. evans and g. ogin 10 Absorption and thermal issues 145 p. willems, d. j. ottaway, and p. beyersdorf 11 Optical scatter 163 j. r. smith and m. e. zucker v vi Contents 12 Reflectivity and thickness optimization 173 i. m. pinto, m. principe, and r. desalvo 13 Beam shaping 196 a. freise 14 Gravitational wave detection 216 d. j. ottaway and s. d. penn 15 High-precision laser stabilization via optical cavities 237 m. j. martin and j. ye 16 Quantum optomechanics 259 g. d. cole and m. aspelmeyer 17 Cavity quantum electrodynamics 280 t. e. northup References 296 Contributors Markus Aspelmeyer University of Vienna, Faculty of Physics, Boltzmanngasse 5, VIENNA 1090, Austria Stefan Ballmer Syracuse University, New York, Department of Physics, SYRACUSE, NY 13244, USA Peter Beyersdorf San Jose State University, Department of Physics and Astronomy, 1, Washington Square, SAN JOSE, CA 95192-0160, USA Vladimir B. Braginsky M. V. Lomonosov Moscow State University, Faculty of Physics, Leninskie Gory, MOSCOW 119991, Russia Shiuh Chao National Tsing Hua University, Institute of Photonics Technologies, 101 Kuangfu Rd, Sec. 2, HSINCHU, Taiwan Garrett D. Cole University of Vienna, Faculty of Physics, Boltzmanngasse 5, VIENNA 1090, Austria Riccardo DeSalvo Universit ´ a degli Studi del Sannio, Via Port’Arsa, 11, 82100 Benevento, Italy Matthew Evans Massachusetts Institute of Technology, LIGO Laboratory MIT, NW22-295, CAMBRIDGE, MA 02139, USA Andreas Freise University of Birmingham, School of Physics and Astronomy, Edgbaston, BIRMINGHAM B15 2TT, UK vii viii List of contributors Michael L. Gorodetsky M. V. Lomonosov, Moscow State University, Faculty of Physics, Leninskie Gory, MOSCOW 119991, Russia Yuri Levin Leiden Observatory, Niels Bohrweg 2, LEIDEN 2300 RA, The Netherlands Iain Martin University of Glasgow, Department of Physics and Astronomy, GLASGOW G12 8QQ, UK Michael J. Martin University of Colorado, Boulder, JILA 440 UCB, BOULDER, CO 80309-0440, USA Tracy E. Northup Universit ¨ at Innsbruck, Institut f ¨ ur Experimentalphysik, Technikerstrasse 25/4, INNSBRUCK 6020, Austria Kenji Numata NASA-Goddard Space Flight Center Code 663, 8800 Greenbelt Rd, GREENBELT, MD 20771, USA Greg Ogin California Institute of Technology, LIGO Laboratory, MS 100-36, Room 252B W. Bridge, PASADENA, CA 91125, USA David J. Ottaway University of Adelaide, School of Chemistry and Physics, ADELAIDE, SOUTH AUSTRALIA 5005, Australia Steven D. Penn Hobart and William Smith Colleges, Department of Physics, 300 Pulteney Street, GENEVA, NY 14456, USA Innocenzo M. Pinto University of Sannio, Department of Engineering, Corso Garibaldi 107, Pal. dell’Aquila Bosco-Lucarelli, BENEVENTO I-82100, Italy Maria Principe Department of Engineering, Corso Garibaldi 107, Pal. dell’Aquila Bosco-Lucarelli, BENEVENTO I-82100, Italy List of contributors ix Stuart Reid University of Glasgow, Department of Physics and Astronomy, GLASGOW G12 8QQ, UK Sheila Rowan University of Glasgow, School of Physics and Astronomy, GLASGOW G12 8QQ, UK Joshua R. Smith Cal State Fullerton, Department of Physics, 800 N State College Blvd, FULLERTON, CA 92831, USA Kentaro Somiya Waseda Institute for Advanced Study, 1-6-1 Nishiwaseda, Shinjuku, TOKYO 169-8050, Japan Sergey P. Vyatchanin M. V. Lomonosov, Moscow State University, Faculty of Physics, Leninskie Gory, MOSCOW 119991, Russia Phil Willems California Institute of Technology, LIGO Laboratory, MS 18-34, PASADENA, CA 91125, USA Kazuhiro Yamamoto Leibniz Universitaet Hannover, Max-Planck-Institut fuer Gravitationsphysik, Callinstrasse 38, HANNOVER D-30167, Germany Jun Ye University of Colorado, Boulder, JILA 440 UCB, BOULDER, CO 80309-0440, USA Michael E. Zucker Massachusetts Institute of Technology, LIGO Laboratory, NW22-295, 185 Albany Street, CAMBRIDGE, MA 02139, USA [...]... methods, and understanding of the underlying physics are ready and can benefit the coating developments for precision measurement Fast turnaround methods for reliable thermal noise measurements on the coatings are needed for optimizing the coating process parameters as well as tailoring the coating materials and their structures, which are crucial to reducing their thermal noise 3 Compendium of thermal noises... reflective coating In addition to intrinsic noises produced by internal properties of optical mirrors, there are also extrinsic noises imprinted onto the output phase due to different nonlinear effects in the bulk and coating of the mirrors As, for example, fluctuations of input power producing fluctuations of thickness and refractive index in the coating due to local heating (the photothermal effect,... the coatings, primarily mechanical loss, lead to noises quite comparable to the noises of the same origin in the substrate Optical Coatings and Thermal Noise in Precision Measurement, eds Gregory M Harry, Timothy Bodiya and Riccardo DeSalvo Published by Cambridge University Press © Cambridge University Press 2012 20 Compendium of thermal noises in optical mirrors 21 3.1 Substrate Brownian thermal noise. .. progress in optical coating technology since the 1970s This chapter introduces coating methods, coating processes, and thin film materials used in high-end coating technologies with the purpose of stimulating further research and development activities on coatings for precision measurement 2.2 Coating methods Various coating methods have been developed to provide films with desired qualities such as good optical. .. is the refractive index of the substrate, n1 and n2 are the refractive indices of the two coating materials, and p is the number of pairs of a high and low index material in the coating Optical Coatings and Thermal Noise in Precision Measurement, eds Gregory M Harry, Timothy Bodiya and Riccardo DeSalvo Published by Cambridge University Press © Cambridge University Press 2012 6 Coating technology 7 High-end... polishing with a high degree of precision Using this method, surface accuracy in tens of nm can be achieved in a relatively fast and reliable way (Kordonski and Golini, 2000) 2.8 Conclusion Optical coating technology for applications in precision measurement is in its initial stage With existing coating technologies developed during the past 30 years for other high-end applications, foundations for coating... properly selecting the materials and designing the layer thicknesses Traditionally, the major application of coatings has been in imaging systems, including coatings on lenses, windows, and filters for purposes such as anti-reflection, band passing, polarization selection, etc (Macleod, 2010; Baumeister, 2004a) With the advent of the laser and its diverse applications, high quality coatings for laser... the heat bath Since ˆ the same coupling is responsible for damping of motion in x, one obtains a proportionality ˆ relation between the microscopic thermal fluctuations of the quantity x and the damping ˆ coefficient for the macroscopic motion when x is driven externally For optomechanical Optical Coatings and Thermal Noise in Precision Measurement, eds Gregory M Harry, Timothy Bodiya and Riccardo DeSalvo... thermal noises in optical mirrors vladimir b braginsky, michael l gorodetsky, and sergey p vyatchanin Phase noise and shot noise are often the fundamental limiting factors of sensitivity in precision optical systems These noises determine the so-called standard quantum limit (Braginsky et al., 2003), see Section 1.4 At the same time the fundamental frequency stability in high-finesse optical resonators... Chapters 15, 16, and 17) Excess optical phase noise is added to a probe optical wave reflected from mirrors forming an optical cavity due to variation of boundary conditions produced by fluctuations of the surface and optical thickness of the multilayer coating We characterize below different effects leading to phase noise starting from fluctuations originating in the mirror’s substrate and in its interferometric . OPTICAL COATINGS AND THERMAL NOISE IN PRECISION MEASUREMENT Thermal noise from optical coatings is a growing area of concern, and overcoming limits to the sensitivity of high -precision measurements. the refractive indices of the two coating materials, and p is the number of pairs of a high and low index material in the coating. Optical Coatings and Thermal Noise in Precision Measurement, eds thermal noise in optical mirrors 1 y. levin 2 Coating technology 6 s. chao 3 Compendium of thermal noises in optical mirrors 20 v. b. braginsky, m. l. gorodetsky, and s. p. vyatchanin 4 Coating