Header

UZH-Logo

Maintenance Infos

U(1) symmetry breaking and violated axial symmetry in TlCuCl3 and other insulating spin systems


Dell'Amore, Raffaele; Schilling, Andreas; Krämer, Karl (2009). U(1) symmetry breaking and violated axial symmetry in TlCuCl3 and other insulating spin systems. Physical Review B, 79(1):014438.

Abstract

We describe the Bose-Einstein condensate of magnetic bosonic quasiparticles in insulating spin systems using a phenomenological standard functional method for T=0. We show that results that are already known from advanced computational techniques immediately follow. The inclusion of a perturbative anisotropy term that violates the axial symmetry allows us to remarkably well explain a number of experimental features of the dimerized spin-1/2 system TlCuCl3. Based on an energetic argument we predict a general intrinsic instability of an axially symmetric magnetic condensate toward a violation of this symmetry, which leads to the spontaneous formation of an anisotropy gap in the energy spectrum above the critical field. We, therefore, expect that a true Goldstone mode in insulating spin systems, i.e., a strictly linear energy-dispersion relation down to arbitrarily small excitations energies, cannot be observed in any real material.

Abstract

We describe the Bose-Einstein condensate of magnetic bosonic quasiparticles in insulating spin systems using a phenomenological standard functional method for T=0. We show that results that are already known from advanced computational techniques immediately follow. The inclusion of a perturbative anisotropy term that violates the axial symmetry allows us to remarkably well explain a number of experimental features of the dimerized spin-1/2 system TlCuCl3. Based on an energetic argument we predict a general intrinsic instability of an axially symmetric magnetic condensate toward a violation of this symmetry, which leads to the spontaneous formation of an anisotropy gap in the energy spectrum above the critical field. We, therefore, expect that a true Goldstone mode in insulating spin systems, i.e., a strictly linear energy-dispersion relation down to arbitrarily small excitations energies, cannot be observed in any real material.

Statistics

Citations

Dimensions.ai Metrics
21 citations in Web of Science®
21 citations in Scopus®
Google Scholar™

Altmetrics

Downloads

96 downloads since deposited on 09 Mar 2009
4 downloads since 12 months
Detailed statistics

Additional indexing

Item Type:Journal Article, refereed, original work
Communities & Collections:07 Faculty of Science > Physics Institute
Dewey Decimal Classification:530 Physics
Scopus Subject Areas:Physical Sciences > Electronic, Optical and Magnetic Materials
Physical Sciences > Condensed Matter Physics
Uncontrolled Keywords:Bose-Einstein condensation, copper compounds, perturbation theory, spin systems, thallium compounds
Language:English
Date:2009
Deposited On:09 Mar 2009 13:12
Last Modified:25 Jun 2022 10:47
Publisher:American Physical Society
ISSN:1098-0121
OA Status:Green
Publisher DOI:https://doi.org/10.1103/PhysRevB.79.014438
  • Content: Accepted Version