Solitary Magnons in the S=52 Antiferromagnet CaFe2O4

C. Stock, E. E. Rodriguez, N. Lee, M. A. Green, F. Demmel, R. A. Ewings, P. Fouquet, M. Laver, Ch. Niedermayer, Y. Su, K. Nemkovski, J. A. Rodriguez-Rivera, and S.-W. Cheong
Phys. Rev. Lett. 117, 017201 – Published 28 June 2016
PDFHTMLExport Citation

Abstract

CaFe2O4 is a S=52 anisotropic antiferromagnet based upon zig-zag chains having two competing magnetic structures, denoted as the A () and B () phases, which differ by the c-axis stacking of ferromagnetic stripes. We apply neutron scattering to demonstrate that the competing A and B phase order parameters result in magnetic antiphase boundaries along c which freeze on the time scale of 1ns at the onset of magnetic order at 200 K. Using high resolution neutron spectroscopy, we find quantized spin wave levels and measure 9 such excitations localized in regions 12 c-axis lattice constants in size. We discuss these in the context of solitary magnons predicted to exist in anisotropic systems. The magnetic anisotropy affords both competing A+B orders as well as localization of spin excitations in a classical magnet.

  • Figure
  • Figure
  • Figure
  • Figure
  • Received 8 March 2016

DOI:https://doi.org/10.1103/PhysRevLett.117.017201

© 2016 American Physical Society

Physics Subject Headings (PhySH)

Condensed Matter, Materials & Applied Physics

Authors & Affiliations

C. Stock1, E. E. Rodriguez2, N. Lee3, M. A. Green4, F. Demmel5, R. A. Ewings5, P. Fouquet6, M. Laver7, Ch. Niedermayer8, Y. Su9, K. Nemkovski9, J. A. Rodriguez-Rivera10,11, and S.-W. Cheong3

  • 1School of Physics and Astronomy and Centre for Science at Extreme Conditions, University of Edinburgh, Edinburgh EH9 3FD, United Kingdom
  • 2Department of Chemistry and Biochemistry, University of Maryland, College Park, Maryland 20742, USA
  • 3Rutgers Center for Emergent Materials and Department of Physics and Astronomy, Rutgers University, 136 Frelinghuysen Road, Piscataway, New Jersey 08854, USA
  • 4School of Physical Sciences, University of Kent, Canterbury CT2 7NH, United Kingdom
  • 5ISIS Facility, Rutherford Appleton Labs, Chilton, Didcot OX11 0QX, United Kingdom
  • 6Institute Laue-Langevin, 6 rue Jules Horowitz, Boite Postale 156, 38042 Grenoble Cedex 9, France
  • 7School of Metallurgy and Materials, University of Birmingham, Birmingham B15 2TT, United Kingdom
  • 8Laboratory for Neutron Scattering, Paul Scherrer Institut, CH-5232 Villigen, Switzerland
  • 9Jülich Centre for Neuton Science JCNS, Forschungszentrum Jülich GmbH, Outstation at MLZ, Lichtenbergstraße 1, D-85747 Garching, Germany
  • 10NIST Center for Neutron Research, National Institute of Standards and Technology, 100 Bureau Drive, Gaithersburg, Maryland 20899, USA
  • 11Department of Materials Science, University of Maryland, College Park, Maryland 20742, USA

Article Text (Subscription Required)

Click to Expand

Supplemental Material (Subscription Required)

Click to Expand

References (Subscription Required)

Click to Expand
Issue

Vol. 117, Iss. 1 — 1 July 2016

Reuse & Permissions
Access Options
CHORUS

Article Available via CHORUS

Download Accepted Manuscript
Author publication services for translation and copyediting assistance advertisement

Authorization Required


×
×

Images

×

Sign up to receive regular email alerts from Physical Review Letters

Log In

Cancel
×

Search


Article Lookup

Paste a citation or DOI

Enter a citation
×