Atoms and Molecules in Strong External Fields (Proc. 172nd WE-Heraeus Seminar, Bad Honnef 1997)

330 Pages·1998·8.816 MB·English

by  P. Schmelcher, W. Schweizer

Atoms and Molecules in
Strong External Fields
Atoms and Molecules in
Strong External Fields
Edited by
P. Schmelcher
University of H eidelberg
Heidelberg, Germany
and
W. Schweizer
University of Tübingen
Tübingen, Germany
KLUWER ACADEMIC PUBLISHERS
NEW YORK, BOSTON, DORDRECHT, LONDON, MOSCOW
eBookISBN: 0-306-47074-8
Print ISBN: 0-306-45811-X
©2002 Kluwer Academic Publishers
New York, Boston, Dordrecht, London, Moscow
All rights reserved
No part of this eBook may be reproduced or transmitted in any form or by any means, electronic,
mechanical, recording, or otherwise, without written consent from the Publisher
Created in the United States of America
Visit Kluwer Online at: http://www.kluweronline.com
and Kluwer's eBookstore at: http://www.ebooks.kluweronline.com
PREFACE
This book contains contributions to the 172. WE-Heraeus-Seminar “Atoms and
Molecules in Strong External Fields,” which took place April 7–11 1997 at the Physik-
zentrum Bad Honnef (Germany).
The designation “strong fields” applies to external static magnetic, and/or electric
fields that are sufficiently intense to cause alterations in the atomic or molecular struc-
ture and dynamics. The specific topics treated are the behavior and properties of atoms
in strong static fields, the fundamental aspects and electronic structure of molecules
in strong magnetic fields, the dynamics and aspects of chaos in highly excited Ryd-
berg atoms in external fields, matter in the atmosphere of astrophysical objects (white
dwarfs, neutron stars), and quantum nanostructures in strong magnetic fields. It is
obvious that the elaboration of the corresponding properties in these regimes causes
the greatest difficulties, and is incomplete even today.
Present-day technology has made it possible for many research groups to study
the behavior of matter in strong external fields, both experimentally and theoreti-
cally, where the phrase “experimentally” includes the astronomical observations. Un-
derstanding these systems requires the development of modern theories and powerful
computational techniques. Interdisciplinary collaborations will be helpful and useful
in developing more efficient methods to understand these important systems. Hence
the idea was to bring together people from different fields like atomic and molecular
physics, theoretical chemistry, astrophysics and all those colleagues interested in aspects
of few-body systems in external fields.
In combination or individually, the articles present a broad and timely review of the
recent progress and the current state of the art in the theoretical, computational, and
experimental studies of atoms and molecules in strong external fields. Astrophysical
aspects related to magnetic white dwarfs and neutron stars are discussed. The com-
putational problems in the strong field regime where the valence electrons experience
electric and magnetic forces of comparable strength are discussed, and some new and
effective methods based on discretization and finite element methods as well as novel
basis set approaches are presented.
New experiments of Rydberg states in strong external fields are reported and re-
lated theoretical and computational aspects as well as the quest of quantum chaos are
discussed. Attention is drawn to the non-separability of the center-of-mass for atomic
and molecular systems in strong magnetic fields. This non-separability gives rise to
effects important in the Rydberg as well as in the astrophysical region. But not only
atoms and molecules in strong magnetic fields are reviewed; this book is rounded off by
the discussion of quantum dots and shallow donor states in strong magnetic fields.
Due to the scientific importance of the subject we hope that the articles presented
v
in this book will prove valuable to a wide scientific audience, ranging from the expe-
rienced researcher to the newcomer. The 172. WE-Heraeus-Seminar brought together
about 50 scientists from many countries. As scientific organizers, we wish to thank
them for their participation, their presentation, and their enthusiasm, which created a
very stimulating and scientifically fruitful atmosphere. We would like to express our
thanks to Jutta Hartmann and Dr. Volker Schafer from the WE-Heraeus-Stiftung for
the unbureaucratic procedure of funding, general organization and realization, and, of
course, to the founders Dr. Wilhelm Heinrich Heraeus and Else Heraeus. We thank
the Deutsche Forschungsgemeinschaft for their financial support for the East-European
participants.
Tübingen and Heidelberg W. Schweizer
P. Schmelcher
vi
CONTENTS
White Dwarfs for Physicists ................................................... 1
D. Koester
Magnetic WhiteDwarfs: Observations in CosmicLaboratories ................... 9
S. Jordan
Hydrogen in Strong Electric and Magnetic Fields and Its Application to Magnetic
White Dwarfs.............................................................. 19
S. Friedrich, P. Faßbinder, I. Seipp and W. Schweizer
Helium Data for Strong Magnetic Fields Obtained by Finite Element Calculations 25
M. Braun, W. Schweizer and H. Elster
The Spectrum of Atomic Hydrogen in Magnetic and Electric Fields of White
Dwarf Stars ................................................................. 31
Peter Faßbinder and Wolfgang Schweizer
Neutron Star Atmospheres ........................................................ 37
G. Pavlov
Hydrogen Atoms in Neutron Star Atmospheres: Analytical Approximations for
Binding Energies ........................................................... 49
A. Y. Potekhin
Absorption of Normal Modes in a Strongly Magnetized Hydrogen Gas ........... 55
T. Bulik and G. Pavlov
Electronic Structure of Light Elements in Strong Magnetic Fields ................ 61
Patrice Pourre, Philippe Arnault and Francois Perrot
From Field-Free Atoms to Finite Molecular Chains in Very Strong Magnetic
Fields..................................................................... 69
M. R. Godefroid
The National High Magnetic Field Laboratory — a Précis ........................ 77
J. E. Crow, J. R. Sabin and N. S. Sullivan
Self-Adaptive Finite Element Techniques for Stable Bound Matter–Antimatter
Systems in Crossed Electric and Magnetic Fields ........................... 83
J. Ackermann
vii
A Computational Method for Quantum Dynamics of a Three-Dimensional Atom
in Strong Fields ........................................................... 89
V. S. Melezhik
Discretization Techniques Applied to Atoms Under Extreme Conditions.......... 95
W. Schweizer, M. Stehle, P. Faßbinder, S. Kulla, I. Seipp and R. Gonzalez
Computer-Algebraic Derivation of Atomic Feynman–Goldstone Expansions ...... 101
S. Fritzsche, B. Fricke and W.-D. Sepp
Scaled-Energy Spectroscopy of Helium and Barium Rydberg Atoms in External
Fields ....................................................................... 109
W. Hogervorst, A. Kips, K. Karremans, T. van der Veldt, G. J. Kuik and
W. Vassen
Atoms in Crossed Fields ......................................................... 121
J.-P. Connerade, K. T. Taylor, G. Droungas, N. E. Karapanagiati, M. S. Zhan,
and J. Rao
Hydrogen-Like Ions Moving in a Strong Magnetic Field........................... 135
V. G. Bezchastnov, G. G. Pavlov and J. Ventura
Center-of-Mass Effects on Atoms in Magnetic Fields .............................. 141
D. Baye and M. Vincke
Scaling Properties for Atoms in External Fields ................................... 153
H. Friedrich
Time Independent and Time Dependent States of Atoms in Static External Fields 169
P. F. O’Mahony, I. Moser, F. Mota-Furtado and J. P. dos Santos
Secular Motion of 3-D Rydberg States in a Microwave Field ...................... 181
A. Buchleitner
Spontaneous Decay of Nondispersive Wave Packets............................... 187
K. Hornberger and A. Buchleitner
lonization of Helium by Static Electric Fields and Short Pulses................... 193
A. Scrinzi
Adiabatic Invariants of Rydberg Electrons in Crossed Fields...................... 199
J. von Milczewski and T. Uzer
Highly Excited Charged Two-Body Systems in a Magnetic Field: A Perturbation
Theoretical Approach to the Classical Dynamics ............................ 207
W. Becken and P. Schmelchcr
Analysis of Quantum Spectra by Harmonic Inversion ............................. 215
J. Main, G. Wunner, V. A. Mandelshtam and H. S. Taylor
Atoms in External Fields: Ghost Orbits, Catastrophes, and Uniform
Semiclassical Approximations ............................................... 223
J. Main and G. Wunner
viii
Quadratic Zeeman Splitting of Highly Excited Relativistic Atomic Hydrogen ..... 233
D. A. Arbatsky and P. A. Braun
Neutral Two-Body Systems of Charged Particles in External Fields .............. 241
L. S. Cederbaurn and P. Schmelcher
Semiclassical Theory of Multielectron Atoms and the Molecular Ion in
Intense External Fields ...................................................... 255
N. H. March
On the Ground State of the Hydrogen Molecule in a Strong Magnetic Field ...... 265
P. Schmelcher and T. Detmer
Hydrogen Molecule in Magnetic Fields: On Excited Sigma States of the Parallel
Configuration.............................................................. 275
T. Detmer, P. Schmelcher, F. K. Diakonos and L. S. Cederbaum
Electronic Properties of Molecules in High Magnetic Fields:
Hypermagnetizabilities of .............................................. 283
K. Runge and J. R. Sabin
Shallow DonorStatesinaMagneticField ....................................... 291
T. O. Klaassen, J. L. Dunn and C. A. Bates
Quantum Dots in Strong Magnetic Fields........................................ 301
P. A. Maksym
Density Functional Theory of Quantum Dots in a Magnetic Field ................ 313
M. Ferconi and G. Vignale
An Analytical Approach to the Problem of an Impurity Electron in a Quantum
Well in the Presence of Electric and Strong Magnetic Fields ................ 319
B. S. Monozon, C. A. Bates and J. L. Dunn
List of Participants ................................................................ 327
Index .............................................................................. 333
ix
Atoms and Molecules in
Strong External Fields