skip to main content

DOE PAGESDOE PAGES

This content will become publicly available on February 24, 2017

Title: Static and dynamical properties of the spin-1/2 equilateral triangular-lattice antiferromagnet Ba3CoSb2O9

We present single-crystal neutron scattering measurements of the spin-1/2 equilateral triangular-lattice antiferromagnet Ba3CoSb2O9. Besides confirming that the Co2+ magnetic moments lie in the ab plane for zero magnetic field and then determining all the exchange parameters of the minimal quasi-2D spin Hamiltonian, we provide conclusive experimental evidence of magnon decay through observation of intrinsic line broadening. Through detailed comparisons with the linear and nonlinear spin-wave theories, we also point out that the large-S approximation, which is conventionally employed to predict magnon decay in noncollinear magnets, is inadequate to explain our experimental observation. Hence, our results call for a new theoretical framework for describing excitation spectra in low-dimensional frustrated magnets under strong quantum effects.
Authors:
 [1] ;  [2] ;  [3] ;  [3] ;  [3] ;  [3] ;  [4] ;  [5] ;  [6] ;  [3]
  1. Univ. of Tennessee, Knoxville, TN (United States); Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
  2. RIKEN, Saitama (Japan)
  3. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
  4. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
  5. Univ. of Tennessee, Knoxville, TN (United States)
  6. Univ. of Tennessee, Knoxville, TN (United States); Florida State Univ., Tallahassee, FL (United States)
Publication Date:
OSTI Identifier:
1267056
Grant/Contract Number:
AC05-00OR22725
Type:
Accepted Manuscript
Journal Name:
Physical Review Letters
Additional Journal Information:
Journal Volume: 116; Journal Issue: 8; Journal ID: ISSN 0031-9007
Publisher:
American Physical Society (APS)
Research Org:
Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States). High Flux Isotope Reactor (HFIR); Spallation Neutron Source
Sponsoring Org:
USDOE Office of Science (SC)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY