MARCEL B Handbook of High-Temperature Superconductor Electronics edited by Neeraj Khare National Physical Laboratory New Delhi, India MARCEL DEKKER, INC. NEW YORK • BASEL Although great care has been taken to provide accurate and current information, neither the author(s) nor the publisher, nor anyone else associated with this publication, shall be liable for any loss, dam- age, or liability directly or indirectly caused or alleged to be caused by this book. The material con- tained herein is not intended to provide specific advice or recommendations for any specific situation. Trademark notice: Product or corporate names may be trademarks or registered trademarks and are used only for identification and explanation without intent to infringe Library of Congress Cataloging-in-Publication Data A catalog record for this book is available from the Library of Congress. ISBN: 0-8247-0823-7 This book is printed on acid-free paper. Headquarters Marcel Dekker, Inc., 270 Madison Avenue, New York, NY 10016, U.S.A. tel: 212-696-9000; fax: 212-685-4540 Distribution and Customer Service Marcel Dekker, Inc., Cimarron Road, Monticello, New York 12701, U.S.A. tel: 800-228-1160; fax: 845-796-1772 Eastern Hemisphere Distribution Marcel Dekker AG, Hutgasse 4, Postfach 812, CH-4001 Basel, Switzerland tel: 41-61-260-6300; fax: 41-61-260-6333 World Wide Web http://www.dekker.com The publisher offers discounts on this book when ordered in bulk quantities. For more information, write to Special Sales/Professional Marketing at the headquarters address above. Copyright © 2003 by Marcel Dekker, Inc. All Rights Reserved. Neither this book nor any part may be reproduced or transmitted in any form or by any means, elec- tronic or mechanical, including photocopying, microfilming, and recording, or by any information storage and retrieval system, without permission in writing from the publisher. Current printing (last digit): 10987654321 PRINTED IN THE UNITED STATES OF AMERICA Copyright © 2003 by Marcel Dekker, Inc. All Rights Reserved. APPLIED PHYSICS A Series of Professional Reference Books Series Editor ALLEN M. HERMANN University of Colorado at Boulder Boulder, Colorado 1. Hydrogenated Amorphous Silicon Alloy Deposition Processes, Werner Luft and Y. Simon Tsuo 2. Thallium-Based High-Temperature Superconductors, edited by Allen M. Hermann and J. V. Yakhmi 3. Composite Superconductors, edited by Kozo Osamura 4. Organic Conductors Fundamentals and Applications, edited by Jean- Pierre Farges 5 Handbook of Semiconductor Electrodeposition, f?. K. Pandey, S. N. Sahu, and S. Chandra 6. Bismuth-Based High-Temperature Superconductors, edited by Hiroshi Maeda and Kazumasa Togano 7. Handbook of High-Temperature Superconductor Electronics, edited by Neeraj Khare Additional Volumes in Preparation Copyright © 2003 by Marcel Dekker, Inc. All Rights Reserved. Preface The discovery of high-temperature superconductors (HTS) exhibiting supercon- ductivity above liquid nitrogen temperature has led to rapid growth in the devel- opment of many special-purpose electronics devices that can be broadly grouped under the umbrella term of “superconductor electronics.” Superconductor electronics promises particular advantages over conven- tional electronics: higher speed, less noise, lower power consumption, and much higher upper-frequency limit. Such characteristics are advantageous in communi- cation technology, high-precision and high-frequency electronics, magnetic field measurement, superfast computers, etc. The potential of several superconductor electronics devices has already been established using low-T c conventional super- conductors. The discovery of cuprate superconductors with higher transition tem- perature and higher energy gap extends the capability of superconductor electron- ics considerably. Rapid advancement in the synthesis of HTS thin films and artificial grain boundary HTS Josephson junctions has elicited considerable interest in the de- velopment of electronic devices found to be very promising for future applications, such as superconducting quantum interference devices (SQUIDs) small microwave, and digital devices. Some of the HTS devices are already on the market. Advances in the physics and material aspects of HTS have been well docu- mented in the form of books and monographs, serving as a starting block for gen- eral readers and beginners. However, the literature was scattered. Thus, this book is vital, bringing together contributions from leaders in different areas of research and development in HTS electronics. The contents are organized to be self-explanatory, comprehensive, and use- ful to both general reader and specialist. In each chapter care has been taken to Copyright © 2003 by Marcel Dekker, Inc. All Rights Reserved. iv Preface introduce basic terminology so that the readers in other fields interested in high- temperature superconductor electronics will find no difficulty in reading it. Pro- fessionals will find it an easily available collection of valuable and relevant infor- mation. The chapters are sequentially organized for use as a text for the study of high-T c devices at the graduate and advanced undergraduate level. Chapter 1 is an introduction to high-T c superconductors, presenting the de- velopments in the discovery of various HTS compounds, its structure, preparation, various properties, and comparison to low-T c superconductors. The developments of various techniques for high-T c thin-film fabrication are described in Chapter 2. Readers interested in knowing the advancements in high-T c film fabrication will find it very interesting and informative. Chapters 3 and 4 present fabrication details and characteristics of multilayer edge junctions and step-edge junctions in high-T c superconducting films. It is not easy to prepare S/I/S Josephson junctions in high-T c as it is usu- ally done in low-T c superconductors (LTS), due to the short coherence length of HTS. Natural grain boundaries in high-T c materials are found to behave as Josephson junctions. Detailed studies of these grain boundaries have led to the development of several techniques for realizing artificial grain boundaries and junctions whose behavior is similar to that of Josephson junctions. Grain bound- aries in HTS are of central importance in numerous applications, such as elec- tronic circuits and sensors and SQUIDs. Also, for many experiments elucidating the physics of high-T c superconductivity, grain boundaries have been used with outstanding success. Chapter 5 discusses the progress in understanding the conduction noise in high-T c superconductors. Chapter 6 reviews noise mechanisms in HTS junctions, experimental techniques, and quantitative data on the noise properties of a range of junctions and devices. Noise in electronic systems sets limits the sensitivity of devices. Supercon- ducting devices offer levels of performance that are difficult or impossible to achieve by conventional methods, but are also subject to limitations due to intrin- sic noise. A full understanding of the noise mechanism remains one of the out- standing tasks in the way of successful high-T c applications. Intrinsic noise is in orders of magnitude greater than the limits imposed by quantum mechanics, and it becomes important to understand the mechanism that causes the excess noise. In recent years, progress in the development of the high-T c SQUID has been remarkable. It is among the first HTS devices to reach the market. The field sen- sitivity achieved in HTS SQUIDs is sufficiently high for several applications in- cluding biomagnetism measurement, nondestructive evaluation, and geophysical measurement. Progress in high-T c rf-SQUIDs and SQUID magnetometer are pre- sented in Chapters 7 and 8. Chapter 9 presents an overview of progress in HTS digital circuits. Chapter 10 reviews the progress in the development of several HTS microwave devices Copyright © 2003 by Marcel Dekker, Inc. All Rights Reserved. Preface v such as filters, delay lines, low loss resonators, and antennas etc. Chapter 11 de- scribes the principles and characteristics of high-T c IR detectors. HTS digital circuits are more suitable for use in single-flux quantum (SFQ) circuits than in LTS ones, because HTS Josephson junctions are naturally over- damped, which means that their I-V curves do not show hysteresis, and the junc- tions in SFQ circuits must be overdamped junctions. The I c R n product of HTS junctions can also be expected to be larger than that of LTS junctions because it intrinsically depends on the gap voltage of the superconductor. For a widespread application of HTS electronics, a package of high-T c com- ponents in closed-cycle cryocoolers is required. Chapter 12 presents advances in the area of cryocoolers and high-T c devices. In order to make this chapter more com- prehensive for beginners, the principles and details of various closed-cycle methods such as the Joule-Thomson, Brayton, Claude, Stirling, Gifford-McMahon, and pulse tube cryocoolers along with their relative merits, are discussed. Finally, the last Chapter 13 presents a summary of the status and future of HTS electronics. This book would have never been possible without the support of all the contributors. I am grateful to all of them for their contributions. In spite of their own busy schedules and commitments, they spared the time to prepare an ex- haustive and critical review. The idea of preparing a book on HTS electronics came after a thought-provoking discussion with Prof. Allen M. Hermann. I am grateful to him for the enthusiasm he created and for his support during the entire course of preparation of the book. I am thankful to the publisher, Marcel Dekker, Inc., for inviting me to edit this book, which indeed proved to be a very interest- ing and rewarding experience. I am also thankful to my production editor, Brian Black, for his editorial support. I have greatly benefited from the experienced advice of Prof. S. Chandra on several occasions and I am grateful to him for all the encouragement and support. Encouragement and guidance received from Prof. S. K. Joshi, Dr. K. Lal, Dr. Praveen Chaudhari, Prof. G. B. Donaldson, Prof. O. N. Srivastava, Prof. E. S. Ra- jagopal, Prof. A. K. Raychaudhuri, and Dr. A. K. Gupta are gratefully acknowl- edged. I am thankful to Dr. N. D. Kataria and Dr. Vijay Kumar for their help and cooperation. Concern and words of appreciation of Prof. O. P. Malviya have been a great source of encouragement for me. Emotional support from my well-wishers par- ticularly came from Priyadarshan Malviya, Pankaj Khare, and Alka Wadhwa. I wish to express my gratitude to my wife, Sangeeta, for her untiring help, cooper- ation, and patience, without which it would not have been possible to complete this book. The smiling face and shining eyes of my little son, Siddharth have been a great source of stress relief for me and always inspired me to devote more time to completing the book. Neeraj Khare Copyright © 2003 by Marcel Dekker, Inc. All Rights Reserved. Contents Preface 1 Introduction to High-Temperature Superconductors Neeraj Khare 2 Epitaxial Growth of Superconducting Cuprate Thin Films David P. Norton 3 High-Temperature Superconducting Multilayer Ramp-Edge Junctions Q. X. Jia 4 Step-Edge Josephson Junctions F. Lombardi and A. Ya. Tzalenchuk 5 Conductance Noise in High-Temperature Superconductors László Béla Kish 6 Noise in High-Temperature Superconductor Josephson Junctions J.C. Macfarlane, L. Hao, and C.M. Pegrum 7 High-Temperature RF SQUIDS V. I. Shnyrkov 8 High-Temperature SQUID Magnetometer Neeraj Khare 9 High-Temperature Superconducting Digital Circuits Mutsuo Hidaka Copyright © 2003 by Marcel Dekker, Inc. All Rights Reserved. 10 High-Temperature Superconductor Microwave Devices Neeraj Khare 11 High-Temperature Superconducting IR Detectors John C. Brasunas 12 Cryocoolers and High-T c Devices Ray Radebaugh 13 High-Temperature Superconductor Electronics: Status and Perspectives Shoji Tanaka viii Copyright © 2003 by Marcel Dekker, Inc. All Rights Reserved. Contributors John C. Brasunas NASA’s Goddard Space Flight Center, Greenbelt, Maryland, U.S.A. L. Hao* Department of Physics and Applied Physics, University of Strathclyde, Glasgow, Scotland Mutsuo Hidaka NEC Corporation, Ibaraki, Japan Q. X. Jia Superconductivity Technology Center, Los Alamos National Laboratory, Los Alamos, New Mexico, U.S.A. Neeraj Khare National Physical Laboratory, New Delhi, India László Béla Kish Texas A&M University, College Station, Texas, U.S.A. F. Lombardi Chalmers Institute of Technology and Göteborg University, Göteborg, Sweden J. C. Macfarlane Department of Physics and Applied Physics, University of Strathclyde, Glasgow, Scotland David P. Norton University of Florida, Gainesville, Florida, U.S.A. C. M. Pegrum Department of Physics and Applied Physics, University of Strathclyde, Glasgow, Scotland *Current affiliation: Centre for Basic Metrology, National Physical Laboratory, Teddington, England Copyright © 2003 by Marcel Dekker, Inc. All Rights Reserved. Ray Radebaugh National Institute of Standards and Technology, Boulder, Colorado, U.S.A. V. I. Shnyrkov Institute for Low Temperature Physics and Engineering, Academy of Sciences, Kharkov, Ukraine Shoji Tanaka Superconductivity Research Laboratory, ISTEC, Tokyo, Japan A. Ya. Tzalenchuk National Physical Laboratory, Middlesex, England x Contributors Copyright © 2003 by Marcel Dekker, Inc. All Rights Reserved. . High- Temperature Superconductor Microwave Devices Neeraj Khare 11 High- Temperature Superconducting IR Detectors John C. Brasunas 12 Cryocoolers and High- T c Devices Ray Radebaugh 13 High- Temperature Superconductor. S. Chandra 6. Bismuth-Based High- Temperature Superconductors, edited by Hiroshi Maeda and Kazumasa Togano 7. Handbook of High- Temperature Superconductor Electronics, edited by Neeraj . term of superconductor electronics. ” Superconductor electronics promises particular advantages over conven- tional electronics: higher speed, less noise, lower power consumption, and much higher