TY - JOUR
T1 - The range of non-Kitaev terms and fractional particles in α-RuCl3
AU - Wang, Yiping
AU - Osterhoudt, Gavin B.
AU - Tian, Yao
AU - Lampen-Kelley, Paige
AU - Banerjee, Arnab
AU - Goldstein, Thomas
AU - Yan, Jun
AU - Knolle, Johannes
AU - Ji, Huiwen
AU - Cava, Robert J.
AU - Nasu, Joji
AU - Motome, Yukitoshi
AU - Nagler, Stephen E.
AU - Mandrus, David
AU - Burch, Kenneth S.
N1 - Funding Information:
We are grateful for numerous discussions with Natalia Perkins, Joshua Heath, Kevin Bedell and Ying Ran. The Raman experiments at 532 nm were performed by Y.W. with support from the National Science Foundation, Award No. DMR-1709987. G.B.O. assisted in the analysis with support from the U.S. Department of Energy (DOE), Office of Science, and Office of Basic Energy Sciences under Award No. DE-SC0018675. Raman experiments performed at 720 nm (T.G. and J.Y.) were achieved by support from the National Science Foundation, Award No. ECCS 1509599. The crystal growth and characterization of α-RuCl3 (P.L.K. and D.M.) with the Gordon and Betty Moore Foundation EPiQS Initiative through Grant GBMF4416. A.B. and S.E.N. were supported by the US DOE Basic Energy Sciences Division of Scientific User Facilities. The work on Cr2Ge2Te6 (H.J. and R.J.C.) at Princeton University is sponsored by an ARO MURI, grant W911NF1210461. The numerical simulations were performed by J.N. with support from Grants-in-Aid for Scientific Research (KAKENHI) (numbers JP15K13533, JP16H02206, JP16K17747, and JP18H04223). Parts of the numerical calculations were performed in the supercomputing systems in ISSP, the University of Tokyo.
Publisher Copyright:
© 2020, The Author(s).
PY - 2020/12/1
Y1 - 2020/12/1
N2 - Significant efforts have focused on the magnetic excitations of relativistic Mott insulators, predicted to realize the Kitaev quantum spin liquid (QSL). This exactly solvable model involves a highly entangled state resulting from bond-dependent Ising interactions that produce excitations which are non-local in terms of spin flips. A key challenge in real materials is identifying the relative size of the non-Kitaev terms and their role in the emergence or suppression of fractional excitations. Here, we identify the energy and temperature boundaries of non-Kitaev interactions by direct comparison of the Raman susceptibility of α-RuCl3 with quantum Monte Carlo (QMC) results for the Kitaev QSL. Moreover, we further confirm the fractional nature of the magnetic excitations, which is given by creating a pair of fermionic quasiparticles. Interestingly, this fermionic response remains valid in the non-Kitaev range. Our results and focus on the use of the Raman susceptibility provide a stringent new test for future theoretical and experimental studies of QSLs.
AB - Significant efforts have focused on the magnetic excitations of relativistic Mott insulators, predicted to realize the Kitaev quantum spin liquid (QSL). This exactly solvable model involves a highly entangled state resulting from bond-dependent Ising interactions that produce excitations which are non-local in terms of spin flips. A key challenge in real materials is identifying the relative size of the non-Kitaev terms and their role in the emergence or suppression of fractional excitations. Here, we identify the energy and temperature boundaries of non-Kitaev interactions by direct comparison of the Raman susceptibility of α-RuCl3 with quantum Monte Carlo (QMC) results for the Kitaev QSL. Moreover, we further confirm the fractional nature of the magnetic excitations, which is given by creating a pair of fermionic quasiparticles. Interestingly, this fermionic response remains valid in the non-Kitaev range. Our results and focus on the use of the Raman susceptibility provide a stringent new test for future theoretical and experimental studies of QSLs.
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U2 - 10.1038/s41535-020-0216-6
DO - 10.1038/s41535-020-0216-6
M3 - Article
AN - SCOPUS:85081254687
SN - 2397-4648
VL - 5
JO - npj Quantum Materials
JF - npj Quantum Materials
IS - 1
M1 - 14
ER -