High-field instability of a field-induced triplon Bose-Einstein condensate

Journal Article · Fri Jan 01 04:00:00 EST 2010 · Physical Review. B, Condensed Matter and Materials Physics

DOI:https://doi.org/10.1103/PHYSREVB.81.020407· OSTI ID:21366650

Rakhimov, Abdulla ^[1]; Sherman, E Ya ^[2]; Kim, Chul Koo ^[3]

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1. Institute of Nuclear Physics, Tashkent 100214 (Uzbekistan)
2. Department of Physical Chemistry, University of Basque Country, 48080 Bilbao (Spain)
3. Institute of Physics and Applied Physics, Yonsei University, Seoul 120-749 (Korea, Republic of)

We study properties of magnetic field-induced Bose-Einstein condensate of triplons as a function of temperature and the field within the Hartree-Fock-Bogoliubov approach including the anomalous density. We show that the magnetization is continuous across the transition, in agreement with the experiment. In sufficiently strong fields the condensate becomes unstable due to triplon-triplon repulsion. As a result, the system is characterized by two critical magnetic fields: one producing the condensate and the other destroying it. We show that nonparabolic triplon dispersion arising due to the gapped bare spectrum and the crystal structure has a strong influence on the phase diagram.

• OSTI ID: 21366650
• Journal Information: Physical Review. B, Condensed Matter and Materials Physics, Journal Name: Physical Review. B, Condensed Matter and Materials Physics Journal Issue: 2 Vol. 81; ISSN 1098-0121
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
BOSE-EINSTEIN CONDENSATION
CONDENSATES
CRYSTAL STRUCTURE
DENSITY
DIAGRAMS
DISPERSIONS
HARTREE-FOCK-BOGOLYUBOV THEORY
INFORMATION
INSTABILITY
MAGNETIC FIELDS
MAGNETIZATION
PHASE DIAGRAMS
PHYSICAL PROPERTIES
SPECTRA
TEMPERATURE DEPENDENCE