Longitudinal magnon in the tetrahedral spin system Cu2Te2O5Br2 near quantum criticality

Research output: Contribution to journal › Research article › Contributed › peer-review

Contributors

  • C. Gros - , Saarland University (Author)
  • P. Lemmens - , Max Planck Institute for Solid State Research, RWTH Aachen University (Author)
  • M. Vojta - , Augsburg University (Author)
  • R. Valentí - , Saarland University (Author)
  • K. Y. Choi - , RWTH Aachen University (Author)
  • H. Kageyama - , The University of Tokyo (Author)
  • Z. Hiroi - , The University of Tokyo (Author)
  • N. V. Mushnikov - , The University of Tokyo (Author)
  • T. Goto - , The University of Tokyo (Author)
  • M. Johnsson - , Stockholm University (Author)
  • P. Millet - , Center for Materials Elaboration and Structural Studies (Author)

Abstract

We present a comprehensive study of the coupled tetrahedra compound Cu2Te2O5Br2 by theory and experiments in external magnetic fields. We report the observation of a longitudinal magnon in Raman scattering in the ordered state close to quantum criticality. We show that the excited tetrahedral-singlet sets the energy scale for the magnetic ordering temperature TN. This energy is determined experimentally. The ordering temperature TN has an inverse-log dependence on the coupling parameters near quantum criticality.

Details

Original languageEnglish
JournalPhysical Review B - Condensed Matter and Materials Physics
Volume67
Issue number17
Publication statusPublished - 8 May 2003
Peer-reviewedYes
Externally publishedYes

Keywords

ASJC Scopus subject areas