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Title: Anisotropic Exchange within Decoupled Tetrahedra in the Quantum Breathing Pyrochlore Ba 3 Yb 2 Zn 5 O 11

Abstract

The low energy spin excitation spectrum of the breathing pyrochlore Ba 3 Yb 2 Zn 5 O 11 has been investigated with inelastic neutron scattering. Several nearly resolution limited modes with no observable dispersion are observed at 250 mK while, at elevated temperatures, transitions between excited levels become visible. To gain deeper insight, a theoretical model of isolated Yb 3+ tetrahedra parametrized by four anisotropic exchange constants is constructed. The model reproduces the inelastic neutron scattering data, specific heat, and magnetic susceptibility with high fidelity. The fitted exchange parameters reveal a Heisenberg antiferromagnet with a very large Dzyaloshinskii-Moriya interaction. Ultimately, using this model, we predict the appearance of an unusual octupolar paramagnet at low temperatures and speculate on the development of inter-tetrahedron correlations.

Authors:
 [1];  [2];  [3];  [4];  [2];  [2];  [5];  [5];  [2];  [2];  [6];  [4]
  1. Univ. of Waterloo, ON (Canada)
  2. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Quantum Condensed Matter Division
  3. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Materials Science & Technology Division
  4. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Quantum Condensed Matter Division; Univ. of Tennessee, Knoxville, TN (United States)
  5. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Chemical and Engineering Materials Division
  6. Univ. of Waterloo, ON (Canada); Perimeter Inst. for Theoretical Physics, Waterloo, ON (Canada)
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Spallation Neutron Source (SNS)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
1260086
Grant/Contract Number:
AC05-00OR22725
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Physical Review Letters
Additional Journal Information:
Journal Volume: 116; Journal Issue: 25; Journal ID: ISSN 0031-9007
Publisher:
American Physical Society (APS)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS

Citation Formats

Rau, J. G., Wu, L. S., May, A. F., Poudel, L., Winn, B., Garlea, V. O., Huq, A., Whitfield, P., Taylor, A. E., Lumsden, M. D., Gingras, M. J. P., and Christianson, A. D. Anisotropic Exchange within Decoupled Tetrahedra in the Quantum Breathing Pyrochlore Ba3Yb2Zn5O11. United States: N. p., 2016. Web. doi:10.1103/PhysRevLett.116.257204.
Rau, J. G., Wu, L. S., May, A. F., Poudel, L., Winn, B., Garlea, V. O., Huq, A., Whitfield, P., Taylor, A. E., Lumsden, M. D., Gingras, M. J. P., & Christianson, A. D. Anisotropic Exchange within Decoupled Tetrahedra in the Quantum Breathing Pyrochlore Ba3Yb2Zn5O11. United States. doi:10.1103/PhysRevLett.116.257204.
Rau, J. G., Wu, L. S., May, A. F., Poudel, L., Winn, B., Garlea, V. O., Huq, A., Whitfield, P., Taylor, A. E., Lumsden, M. D., Gingras, M. J. P., and Christianson, A. D. 2016. "Anisotropic Exchange within Decoupled Tetrahedra in the Quantum Breathing Pyrochlore Ba3Yb2Zn5O11". United States. doi:10.1103/PhysRevLett.116.257204. https://www.osti.gov/servlets/purl/1260086.
@article{osti_1260086,
title = {Anisotropic Exchange within Decoupled Tetrahedra in the Quantum Breathing Pyrochlore Ba3Yb2Zn5O11},
author = {Rau, J. G. and Wu, L. S. and May, A. F. and Poudel, L. and Winn, B. and Garlea, V. O. and Huq, A. and Whitfield, P. and Taylor, A. E. and Lumsden, M. D. and Gingras, M. J. P. and Christianson, A. D.},
abstractNote = {The low energy spin excitation spectrum of the breathing pyrochlore Ba3Yb2Zn5O11 has been investigated with inelastic neutron scattering. Several nearly resolution limited modes with no observable dispersion are observed at 250 mK while, at elevated temperatures, transitions between excited levels become visible. To gain deeper insight, a theoretical model of isolated Yb3+ tetrahedra parametrized by four anisotropic exchange constants is constructed. The model reproduces the inelastic neutron scattering data, specific heat, and magnetic susceptibility with high fidelity. The fitted exchange parameters reveal a Heisenberg antiferromagnet with a very large Dzyaloshinskii-Moriya interaction. Ultimately, using this model, we predict the appearance of an unusual octupolar paramagnet at low temperatures and speculate on the development of inter-tetrahedron correlations.},
doi = {10.1103/PhysRevLett.116.257204},
journal = {Physical Review Letters},
number = 25,
volume = 116,
place = {United States},
year = 2016,
month = 6
}

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