Table Of ContentSECOND EDITION
ThermaPl hysic·s
CHARLES KITTEL/ HERBERT KROEMER
Thermal
Physics
SECOND EDITION
Thermal
Physics
Charles Kittel
Herbert Kroemer
University of California
[E
W. H. Freeman and Company
New York
Sponsoring Editor: Peter Renz
Project Editor: Nancy Flight
Manuscript Editor: Ruth Veres
Designers: Gary A. Head and Sharon H. Smith
Production Coordinator: Frank Mitchell
Illustration Coordinator: Batyah Janowski
Anist: Felix Cooper
Compositor: Syntax International
Printer and Binder: Halliday Litho
Library of Congress Cataloging in Publication Data
Kittel, Charles.
Thermal physics.
Bibliography: p.
Includes index.
I. Statistical thermodynamics. I. Kroemer,
Herbert, 1928- joint author. II. Title.
QC31 l.5.K52 1980 536'.7 79-16677
ISBN 0-7167-1088-9
Copyright© 1980 by W. H. Freeman and Company
No part of this book may be reproduced by any
mechanical, photographic, or electronic process, or in
the form of a phonographic recording, nor may it be
stored in a retrieval system, transmitted, or otherwise
copied for public or private use, without written
permission from the publisher.
Printed in the United State of America
11 12 13 14 15 16 VB 9 9 8 7 6 5 4 3 2 1 0
About the Authors
Charles Kittel has taught solid state physics at the University of California
at Berkeley since 1951, having previously been at the Bell Laboratories. His
undergraduate work in physics was done at M.I.T. and at the Cavendish
Laboratory of Cambridge University. His Ph.D. research was in theoretical
nuclear physics with Professor Gregory Breit at the University of Wisconsin.
He has been awarded three Guggenheim fellowships, the Oliver Buckley Prize
for Solid State Physics, and, for contributions to teaching, the Oersted Medal
of the American Association of Physics Teachers. He is a member of the
National Academy of Science and of the American Academy of Arts and
Sciences. His research has been in magnetism, magnetic resonance, semicon
ductors, and the statistical mechanics of solids.
Herbert Kroemer is Professor of Electrical Engineering at the University of
California at Santa Barbara. His background and training are in solid state
physics. He received a Ph.D. in physics in 1952f rom the University of Gottingen
in Germany with a thesis on hot electron effects in the then new transistor.
From 1952 through 1968 he worked in several semiconductor research labora
tories in Germany and the United States. In 1968 he became Professor of
Electrical Engineering at the University of Colorado; he came to UCSB in
1976. His research has been in the physics and technology of semiconductors
and semiconductor devices, including high-frequency transistors, negative
mass effects in semiconductors, injection lasers, the Gunn effect, electron-hole
drops, and semiconductor heterojunctions.
V
Preface
This book gives an elementary account of thermal physics. The subject is
simple, the methods are powerful, and the results have broad applications.
Probably no other physical theory is used more widely throughout science and
engineering.
We have written for undergraduate students of physics and astronomy, and
for electrical engineering students generally. These fields for our purposes have
strong common bonds, most notably a concern with Fermi gases, whether in
semiconductors, metals, stars, or nuclei. We develop methods (not original, but
not easily accessible elsewhere) that are well suited to these fields. We wrote
the book in the first place because we were delighted by the clarity of the
"new" methods as compared to those we were taught when we were students
ourselves.
The second edition is substantially rewritten and revised from the first
edition, which, although warmly accepted, suffered from the concentration
of abstract ideas at the beginning. In the new structure the free energy, the
partition function, and the Planck distribution are developed before the chem
ical potential. Real problems can now be solved much earlier. We have
added chapters on applications to semiconductors, binary mixtures, transport
theory, cryogenics, and propagation. The treatment of heat and work is new
and will be helpful to those concerned with energy conversion processes. Many
more examples and problems are given, but we have not introduced problems
where they do not contribute to the main line of advance. For this edition
an instructor's guide is available from the publisher, upon request from the
instructor.
This edition has been tested extensively over the past few years in classroom
use. We have not emphasized several traditional topics, some because they are
no longer useful and some because their reliance on classical statistical me
chanics would make the course more difficult than we believe a first course
should be. Also, we have avoided the use of combinatorial methods where they
are unnecessary.
For a one quarter course for physics undergraduates, we suggest most of
Chapters 1 through 10, plus 14. The Debye theory could be omitted from
""
viii Preface
Chapter 4 and the Boltzmann transport equation from Chapter 14. For a one
quarter course for electrical engineers, we suggest Chapter 13 at any time after
the discussion of the Fermi gas in Chapter 7. The material of Chapter 13 does
not draw on Chapter 4. The scope of the book is ample for a one semester
course, and here the pace can be relaxed.
Notation and units: We generally use the SI and CGS systems in parallel.
We do not use the calorie. The kelvin temperature T is related to the funda
mental temperature r by r = k8 T, and the conventional entropy S is related
to the fundamental entropy a by S = k8a. The symbol log will denote natural
logarithm throughout, simply because In is less expressive when set in type.
The notation (18) refers to Equation (18) of the current chapter, but (3.18)
refers to Equation (18) of Chapter 3.
The book is the successor to course notes developed with the assistance of
grants by the University of California. Edward M. Purcell contributed many
ideas to the first edition. We benefited from review of the second edition by
Seymour Geller, Paul L. Richards, and Nicholas Wheeler. Help was given by
Ibrahim Adawi, Bernard Black, G. Domokos, Margaret Geller, Cameron
Hayne, K. A. Jackson, S. Justi, Peter Kittel, Richard Kittler, Martin J. Klein,
Ellen Leverenz, Bruce H.J. McKellar, F. E. O'Meara, Norman E. Phillips,
B. Roswell Russell, T. M. Sanders, B. Stoeckly, John Verhoogen, John Wheatley,
and Eyvind Wichmann. We thank Carol Tung for the typed manuscript and
Sari Wilde for her help with the index.
Berkeley and Santa Barbara Charles Kittel
H erhert Kroemer
Note to the Student
For minimum coverage of the concepts presented in each chapter, the authors
recommend the following exercises. Chapter 2: 1, 2, 3; Chapter 3: 1, 2, 3, 4, 8,
11; Chapter 4: 1, 2, 4, 5, 6, 8; Chapter 5: 1, 3, 4, 6, 8; Chapter 6: 1, 2, 3, 6, 12,
14, 15; Chapter 7: 2, 3, 5, 6, 7, 11; Chapter 8: 1, 2, 3, 5, 6, 7; Chapter 9: l, 2, 3:
Chapter 10: l, 2, 3; Chapter 11: 1, 2, 3; Chapter 12: 3, 4, 5; Chapter 13: 1, 2,
3, 7, 8, 10; Chapter 14: 1, 3, 4, 5; Chapter 15: 2, 3, 4, 6.
ix
Contents
Guide to Fundamental Definitions xm
General References xv
Introduction
Chapter 1 States of a Model System 5
Chapter 2 Entropy and Temperature 27
Chapter 3 Boltzmann Distribution and Helmholtz
Free Energy 55
Chapter 4 Thermal Radiation and Planck Distribution 87
Chapter 5 Chemical Potential and Gibbs Distribution 117
Chapter 6 Ideal Gas 151
Chapter 7 Fermi and Bose Gases 181
Chapter 8 Heat and Work 225
Chapter 9 Gibbs Free Energy and Chemical Reactions 261
Chapter 10 Phase Transformations 275
Chapter 11 Binary Mixtures 309
Chapter 12 Cryogenics 333
Chapter 13 Semiconductor Statistics 353
Chapter 14 Kinetic Theory 389
Chapter 15 Propagation 423
Appendix A Some Integrals Containing Exponentials 439
Appendix B Temperature Scales 445
xi
