1
|
Gitgeatpong G, Zhao Y, Piyawongwatthana P, Qiu Y, Harriger LW, Butch NP, Sato TJ, Matan K. Nonreciprocal Magnons and Symmetry-Breaking in the Noncentrosymmetric Antiferromagnet. Phys Rev Lett 2017; 119:047201. [PMID: 29341758 DOI: 10.1103/physrevlett.119.047201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2017] [Indexed: 06/07/2023]
Abstract
Inelastic neutron scattering measurements were performed to study spin dynamics in the noncentrosymmetric antiferromagnet α-Cu_{2}V_{2}O_{7}. For the first time, nonreciprocal magnons were experimentally measured in an antiferromagnet. These nonreciprocal magnons are caused by the incompatibility between anisotropic exchange and antisymmetric Dzyaloshinskii-Moriya interactions, which arise from broken symmetry, resulting in a collinear ordered state but helical spin dynamics. The nonreciprocity introduces the difference in the phase velocity of the counterrotating modes, causing the opposite spontaneous magnonic Faraday rotation of the left- and right-propagating spin waves. The breaking of spatial inversion and time reversal symmetry is revealed as a magnetic-field-induced asymmetric energy shift, which provides a test for the detailed balance relation.
Collapse
Affiliation(s)
- G Gitgeatpong
- Department of Physics, Faculty of Science, Mahidol University, Bangkok 10400, Thailand
- ThEP, Commission of Higher Education, Bangkok 10400, Thailand
- Department of Physics, Faculty of Science and Technology, Phranakhon Rajabhat University, Bangkok 10220, Thailand
| | - Y Zhao
- Department of Materials Science and Engineering, University of Maryland, College Park, Maryland 20742, USA
- NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA
| | - P Piyawongwatthana
- Department of Physics, Faculty of Science, Mahidol University, Bangkok 10400, Thailand
| | - Y Qiu
- NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA
| | - L W Harriger
- NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA
| | - N P Butch
- NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA
| | - T J Sato
- IMRAM, Tohoku University, Sendai, Miyagi 980-8577, Japan
| | - K Matan
- Department of Physics, Faculty of Science, Mahidol University, Bangkok 10400, Thailand
- ThEP, Commission of Higher Education, Bangkok 10400, Thailand
| |
Collapse
|
2
|
Helton JS, Matan K, Shores MP, Nytko EA, Bartlett BM, Qiu Y, Nocera DG, Lee YS. Dynamic scaling in the susceptibility of the spin-1/2 kagome lattice antiferromagnet herbertsmithite. Phys Rev Lett 2010; 104:147201. [PMID: 20481955 DOI: 10.1103/physrevlett.104.147201] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2010] [Revised: 03/11/2010] [Indexed: 05/29/2023]
Abstract
The spin-1/2 kagome lattice antiferromagnet herbertsmithite, ZnCu(3)(OH)(6)Cl(2), is a candidate material for a quantum spin liquid ground state. We show that the magnetic response of this material displays an unusual scaling relation in both the bulk ac susceptibility and the low energy dynamic susceptibility as measured by inelastic neutron scattering. The quantity chiT(alpha) with alpha approximately 0.66 can be expressed as a universal function of H/T or omega/T. This scaling is discussed in relation to similar behavior seen in systems influenced by disorder or by the proximity to a quantum critical point.
Collapse
Affiliation(s)
- J S Helton
- Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | | | | | | | | | | | | | | |
Collapse
|
3
|
Helton JS, Matan K, Shores MP, Nytko EA, Bartlett BM, Yoshida Y, Takano Y, Suslov A, Qiu Y, Chung JH, Nocera DG, Lee YS. Spin dynamics of the spin-1/2 kagome lattice antiferromagnet ZnCu3(OH)6Cl2. Phys Rev Lett 2007; 98:107204. [PMID: 17358563 DOI: 10.1103/physrevlett.98.107204] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2006] [Indexed: 05/14/2023]
Abstract
We have performed thermodynamic and neutron scattering measurements on the S=1/2 kagomé lattice antiferromagnet ZnCu3(OH)6Cl2. The susceptibility indicates a Curie-Weiss temperature of theta CW approximately = -300 K; however, no magnetic order is observed down to 50 mK. Inelastic neutron scattering reveals a spectrum of low energy spin excitations with no observable gap down to 0.1 meV. The specific heat at low-T follows a power law temperature dependence. These results suggest that an unusual spin liquid state with essentially gapless excitations is realized in this kagomé lattice system.
Collapse
Affiliation(s)
- J S Helton
- Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
4
|
Matan K, Grohol D, Nocera DG, Yildirim T, Harris AB, Lee SH, Nagler SE, Lee YS. Spin waves in the frustrated kagomé lattice antiferromagnet KFe3(OH)6(SO4)2. Phys Rev Lett 2006; 96:247201. [PMID: 16907274 DOI: 10.1103/physrevlett.96.247201] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2006] [Indexed: 05/11/2023]
Abstract
The spin wave excitations of the S=5/2 kagomé lattice antiferromagnet KFe3(OH)6(SO4)2 have been measured using high-resolution inelastic neutron scattering. We directly observe a flat mode which corresponds to a lifted "zero energy mode," verifying a fundamental prediction for the kagomé lattice. A simple Heisenberg spin Hamiltonian provides an excellent fit to our spin wave data. The antisymmetric Dzyaloshinskii-Moriya interaction is the primary source of anisotropy and explains the low-temperature magnetization and spin structure.
Collapse
Affiliation(s)
- K Matan
- Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | | | | | | | | | | | | | | |
Collapse
|
5
|
Chou FC, Cho JH, Lee PA, Abel ET, Matan K, Lee YS. Thermodynamic and transport measurements of superconducting Na0.3CoO2.1.3H2O single crystals prepared by electrochemical deintercalation. Phys Rev Lett 2004; 92:157004. [PMID: 15169310 DOI: 10.1103/physrevlett.92.157004] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2003] [Indexed: 05/24/2023]
Abstract
Superconducting single crystal samples of Na0.3CoO2.1.3H(2)O have been produced using an electrochemical technique which dispenses with the usual bromine chemical deintercalation method. In fully hydrated crystals, susceptibility and specific heat measurements confirm that bulk superconductivity has been achieved. The extracted normal state density of states indicates Fermi-liquid behavior with strong mass enhancement and a modest Wilson ratio. Measurements of H(c2) for H parallel c and H parallel ab reveal significant anisotropy, and the extracted value for the coherence length is about 100 A, consistent with an extremely narrow bandwidth.
Collapse
Affiliation(s)
- F C Chou
- Center for Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | | | | | | | | | | |
Collapse
|