Low Temperature Physics: 33, 745 (2007); https://doi.org/10.1063/1.2780166 (12 pages)
Физика Низких Температур: Том 33, Выпуск 9 (Сентябрь 2007), c. 982-996    ( к оглавлению , назад )

Universal properties of highly frustrated quantum magnets in strong magnetic fields

Oleg Derzhko1,2,3, Johannes Richter2,3, Andreas Honecker4, and Heinz-Jürgen Schmidt5

1Institute for Condensed Matter Physics, National Academy of Sciences of Ukraine 1 Svientsitskii Str., L'viv 79011, Ukraine

2Max-Planck-Institut für Physik komplexer Systeme, 38 Nöthnitzer Str., Dresden 01187, Germany

3Institut für Theoretische Physik, Universität Magdeburg, P.O. Box 4120, Magdeburg 39016, Germany
E-mail: Johannes.Richter@Physik.Uni-Magdeburg.DE

4Institut für Theoretische Physik, Georg-August-Universitдt Göttingen 1 Friedrich-Hund-Platz, Göttingen 37077, Germany

5Fachbereich Physik, Universität Osnabrück, 7 Barbara Str., Osnabrück 49069, Germany

Received December 12, 2006


The purpose of the present paper is two-fold. On the one hand, we review some recent studies on the low-temperature strong-field thermodynamic properties of frustrated quantum spin antiferromagnets which admit the so-called localized-magnon eigenstates. One the other hand, we provide some complementary new results. We focus on the linear independence of the localized-magnon states, the estimation of their degeneracy with the help of auxiliary classical lattice–gas models and the analysis of the contribution of these states to thermodynamics.

PACS: 75.10.Jm Quantized spin models;
PACS: 75.45.+j Macroscopic quantum phenomena in magnetic systems;
PACS: 75.50.Ee Antiferromagnetics.

Key words: frustrated Heisenberg antiferromagnets, strong magnetic field, localized-magnon states, classical lattice-gas models.