Spin-wave induced phonon resonance in multiferroic BiFeO₃

Journal Article · Fri Jun 29 04:00:00 EDT 2018 · arXiv.org Repository

OSTI ID:1466719

Xu, Z. ^[1]; Schneeloch, J. A. ^[2]; Wen, Jinsheng ^[3]; Matsuda, M. ^[4]; Pajerowski, D. ^[4]; Winn, B. L. ^[4]; Zhao, Yang ^[5]; Stock, Christopher ^[6]; Gehring, Peter M. ^[5]; Ushiyama, T. ^[7]; Yanagisawa, Y. ^[7]; Tomioka, Y. ^[7]; Ito, T. ^[7]; Gu, Genda ^[8]; Birgeneau, R. J. ^[9]; Xu, Guangyong ^[10]

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1. Brookhaven National Lab. (BNL), Upton, NY (United States). Condensed Matter Physics and Materials Science Department; National Inst. of Standards and Technology (NIST), Gaithersburg, MD (United States). Center for Neutron Research; Univ. of Maryland, College Park, MD (United States). Department of Materials Science and Engineering; Univ. of California, Berkeley, CA (United States). Physics Department; Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Materials Science Division
2. Brookhaven National Lab. (BNL), Upton, NY (United States). Condensed Matter Physics and Materials Science Department; Stony Brook Univ., NY (United States). Dept. of Physics
3. Nanjing Univ. (China); Univ. of California, Berkeley, CA (United States). Physics Department; Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Materials Science Division
4. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Quantum Condensed Matter Division
5. National Inst. of Standards and Technology (NIST), Gaithersburg, MD (United States). Center for Neutron Research; Univ. of Maryland, College Park, MD (United States). Department of Materials Science and Engineering
6. Univ. of Edinburgh, Scotland (United Kingdom). School of Physics and Astronomy
7. National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba (Japan)
8. Brookhaven National Lab. (BNL), Upton, NY (United States). Condensed Matter Physics and Materials Science Department
9. Univ. of California, Berkeley, CA (United States). Physics Department; Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Materials Science Division
10. Brookhaven National Lab. (BNL), Upton, NY (United States). Condensed Matter Physics and Materials Science Department; National Inst. of Standards and Technology (NIST), Gaithersburg, MD (United States). Center for Neutron Research

In this paper, we report the direct observation of a "resonance" mode in the lowest-energy optic phonon very near the zone center around (111) in the multiferroic BiFeO$$_3$$ using neutron scattering methods. The phonon scattering intensity is enhanced when antiferromagnetic (AFM) order sets in at T$$_N = 640$$~K, and it increases on cooling. This "resonance" is confined to a very narrow region in energy-momentum space where no spin-wave excitation intensity is expected, and it can be modified by an external magnetic field. In conclusion, our results suggest the existence of a novel coupling between the lattice and spin fluctuations in this multiferroic system in which the spin-wave excitations are mapped onto the lattice vibrations via the Dzyaloshinskii-Moriya (DM) interaction.

• Research Organization: Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22). Materials Sciences & Engineering Division
• DOE Contract Number: AC02-05CH11231; SC0012704
• OSTI ID: 1466719
• Journal Information: arXiv.org Repository, Journal Name: arXiv.org Repository Vol. 2018; ISSN 9999-0017
• Publisher: Cornell University
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY