Halilov (ed), Physics of spin in solids.2004

H. Szymczak, Institute of Physics, Al. Lotnikow 32/46, PL-02-668 Warsaw, Poland

M. Pekala, Department of Chemistry, University of Warsaw, Al. Zwirki i Wigury 101, PL-02-089 Warsaw, Poland

Silke Biermann, Centre de Physique Theorique, Ecole Polytechnique, 91128 Palaiseau, France

Ferdi Aryasetiawan, Research Institute for Computational Sciences, AIST,

1-1-1 Umezono, Tsukuba Central 2, Ibaraki 305-8568, Japan

Antoine Georges, Centre de Physique Theorique,

Ecole Polytechnique, 91128 Palaiseau, France

S.L. Molodtsov, Institut fr Festkrperphysik, Technische Universitt Dresden,

D-01062 Dresden, Germany

M.D. Johannes, Center for Computational Material Science Naval Research Laboratory

Washington, D.C. 20375

Siyavush Azakov, Institute of Physics, Azerbaijan Academy of Sciences, Baku-370143, Azerbaijan

Nicholas Kioussis, Department of Physics

California State University Northridge, California 91330-8268

Yan Luo, Department of Physics

California State University Northridge, California 91330-8268

Claudio Verdozzi, Department of Physics

California State University Northridge, California 91330-8268

F. M. Grosche, Department of Physics

Royal Holloway, University of London, Egham, UK

D. Moroni-Klementowicz, Department of Physics

Royal Holloway, University of London, Egham, UK

R. Burrell, Department of Physics

Royal Holloway, University of London, Egham, UK

D. Fort, School of Engineering, Metallurgy and Materials, University of Birmingham, Birmingham, UK

J. Awaka, Department of Materials Science and Engineering,

Muroran Institute of Technology, 27-1 Mizumoto-cho, Muroran, Hokkaido 050-8585, Japan

S. Nagata, Department of Materials Science and Engineering, Muroran Institute of Technology, 27-1 Mizumoto-cho, Muroran, Hokkaido 050-8585, Japan

H. Q. Yuan, Max-Planck-Institute for Chemical Physics of Solids, N¨othnitzer Str. 40, D-01187 Dresden, Germany

M. Deppe, Max-Planck-Institute for Chemical Physics of Solids, N¨othnitzer Str. 40, D-01187 Dresden, Germany

C. Geibel, Max-Planck-Institute for Chemical Physics of Solids, N¨othnitzer Str. 40, D-01187 Dresden, Germany

G. Sparn, Max-Planck-Institute for Chemical Physics of Solids, N¨othnitzer Str. 40, D-01187 Dresden, Germany

F. Steglich, Max-Planck-Institute for Chemical Physics of Solids, N¨othnitzer Str. 40, D-01187 Dresden, Germany

Lars Nordstr¨om, Department of Physics,

Uppsala University, Box 530, S-751 21 Uppsala, Sweden

Till Burkert, Department of Physics,

Uppsala University, Box 530, S-751 21 Uppsala, Sweden

xii Contributing Authors

Massiliano Colarieti-Tosti, Department of Physics, Uppsala University, Box 530, S-751 21 Uppsala, Sweden

Olle Eriksson, Department of Physics,

Uppsala University, Box 530, S-751 21 Uppsala, Sweden

I.I. Mazin,Center for Computational Materials Science Naval Research Laboratory

Washington, DC 20375, USA

D.J. Singh,Center for Computational Materials Science Naval Research Laboratory

Washington, DC 20375, USA

A. Aguayo,Center for Computational Materials Science Naval Research Laboratory

Washington, DC 20375, USA

I. N. Askerzade, Institute of Physics, Azerbaijan National Academy of Sciences, Baku-370143, Azerbaijan

A. Perlov,University of Munich, Butenandstrasse 5-13, D-81377, Munich, Germany

S. Chadov,University of Munich, Butenandstrasse 5-13, D-81377, Munich, Germany

H. Ebert,University of Munich, Butenandstrasse 5-13, D-81377, Munich, Germany

L. Chioncel,University of Nijmegen, NL-6526 ED Nijmegen, The Netherlands

A.Lichtenstein,University of Nijmegen, NL-6526 ED Nijmegen, The

Netherlands

M. Katsnelson,Uppsala University, P.O.Box 530, S-751 21 Uppsala,

Sweden

K. I. Kugel, Institute for Theoretical and Applied Electrodynamics, Russian Academy of Sciences

Izhorskaya str. 13/19, Moscow 125412, Russia

A.L. Rakhmanov, Institute for Theoretical and Applied Electrodynamics, Russian Academy of Sciences

Izhorskaya str. 13/19, Moscow 125412, Russia

A.O. Sboychakov, Institute for Theoretical and Applied Electrodynamics, Russian Academy of Sciences Izhorskaya str. 13/19, Moscow 125412, Russia

M. Yu. Kagan, Kapitza Institute for Physical Problems, Russian Academy of Sciences Kosygina str. 2, Moscow, 119334 Russia

I. V. Brodsky, Kapitza Institute for Physical Problems, Russian Academy of Sciences Kosygina str. 2, Moscow, 119334 Russia

A. V. Klaptsov, Kapitza Institute for Physical Problems, Russian Academy of Sciences Kosygina str. 2, Moscow, 119334 Russia

E. M. Kerimova, Institute of Physics, National Academy of Sciences of Azerbaijan, Baku-370143, Azerbaijan

S. N. Mustafaeva, Institute of Physics, National Academy of Sciences of Azerbaijan, Baku-370143, Azerbaijan

A. I. Jabbarly, Institute of Physics, National Academy of Sciences of Azerbaijan, Baku-370143, Azerbaijan

G. Sultanov, Institute of Physics, National Academy of Sciences of Azerbaijan, Baku-370143, Azerbaijan

A.I.Gasanov, Institute of Physics, National Academy of Sciences of Azerbaijan, Baku-370143, Azerbaijan

R. N. Kerimov, Institute of Physics, National Academy of Sciences of Azerbaijan, Baku-370143, Azerbaijan

R.T. Tagiyeva, Institute of Physics Azerbaijan National Academy of Sciences, Baku-370143, Azerbaijan

S. V. Halilov, Center for Computational Materials Science, Naval Research Laboratory, Washington, DC 20375, and Department of Materials Science and Engineering, University of Pennsylvania, Philadelphia, PA 19104

Preface

In 1925, H. Ulenbeck and S. Goudsmith suggested the idea of spin as a kind of intrinsic moment in electrons, thus establishing a fundamental building block in the physics of magnetic phenomena in solids. Currently, research in the area of magnetism is largely motivated by the needs of technology. However, research e orts outside the scope of technological needs are useful for the advancement of the physics of spin itself. It is well known that spin-dependent/related phenomena such as magneto-resistance, superconductivity, magneto-optics and others have been under intense theoretical and experimental investigation resulting in the creation of new devices in the area of digital recording and spin-dependent transport-based technologies. On the other hand, further development of experimental research techniques enhanced the accuracy of measurements such as, for example, scanning tunneling microscopy, exchange force microscopy, angleand spin-resolved photoemission, scattering of neutrons and electrons on magnetic type of excitations, challenging physicists to improve the interpretations of results on a computational rather than qualitative basis. Some examples are new quantitative understandings of phenomena such as the interplay of di erent types of low-lying excitations involving charge, spin, and lattice degrees of freedom in manganites and conventional superconductors, the unique role of quantum spin fluctuations in thermodynamics and transport properties of unconventional superconductors and weak ferromagnets, the influence of electron correlations on order/disorder of magnetic nanoclusters or quantum dots, and co-existance of non-uniform magnetic ordering and superconductivity.

This book reviews a rather limited selection of recent progress made in the vast field of magnetism. The list of chapters comprise such issues as: new many-body theoretical developments and applications designed to more accurately describe the ground state and excitations of strongly correlated systems on arbitrary energy scales, spin-dependent tunnel currents and proximity e ects at the interface of magnetic materials and superconductors, application of first-principle calculations to

xv

explore spin-dependent material properties close to a quantum critical point such as spectrum of magnetic fluctuations, magneto-crystalline anisotropy, non-uniform magnetism, search for quantum phase transitions in narrow-band metals.

SAMED HALILOV

Washington, D.C.

February, 2004

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FULDE-FERRELL-LARKIN- OVCHINNIKOV-LIKE STATE IN FERROMAGNET - SUPERCONDUCTOR PROXIMITY SYSTEM

B. L. Gy¨or y

H. H. Wills Physics Laboratory, University of Bristol, Tyndall Ave., Bristol BS8 1TL, UK

Centre for Computational Materials Science, TU Wien, Gertreidemarkt 9/134, A-1060 Wien, Austria

M. Krawiec

Institute of Physics and Nanotechnology Center, Maria Curie-Sklodowska University, Pl. Marii Curie-Sklodowskiej 1, 20-031 Lublin, Poland

J.F. Annett

H.H. Wills Physics Laboratory, University of Bristol, Tyndall Ave., Bristol BS8 1TL, UK

Abstract We discuss some properties of the ferromagnet - superconductor proximity system. In particular, the emphasis is put on the physics of the Fulde-Ferrell-Larkin-Ovchinnikov (F F LO) like state. In addition to Andreev reflections it features a number of unusual thermodynamic and transport properties, like: oscillatory behavior of the pairing amplitude, density of states and superconducting transition temperature as a function of the ferromagnet thickness. Surprisingly, under certain conditions spontaneous spin polarized current is generated in the ground state of such a system. We provide some informations regarding experimental observations of this exotic state.

Keywords: Proximity e ect, Fulde-Ferrell-Larkin-Ovchinnikov state

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S. Halilov (ed.), Physics of Spin in Solids: Materials, Methods and Applications, 1–16.C 2004 Kluwer Academic Publishers. Printed in the Netherlands.