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Title: Polarization-resolved Raman spectroscopy of α RuCl 3 and evidence of room-temperature two-dimensional magnetic scattering

Journal Article · · Physical Review B
 [1];  [2];  [3];  [4];  [5]; ORCiD logo [3]; ORCiD logo [6];  [3];  [2]; ORCiD logo [7]
  1. The Ohio State Univ., Columbus, OH (United States); National Inst. of Standards and Technology (NIST), Gaithersburg, MD (United States)
  2. National Inst. of Standards and Technology (NIST), Gaithersburg, MD (United States)
  3. Univ. of Tennessee, Knoxville, TN (United States); Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
  4. National Inst. of Standards and Technology (NIST), Gaithersburg, MD (United States); Univ. of Maryland, College Park, MD (United States)
  5. Towson Univ., MD (United States); National Inst. of Standards and Technology (NIST), Gaithersburg, MD (United States)
  6. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
  7. The Ohio State Univ., Columbus, OH (United States)

Polarization-resolved Raman spectroscopy was performed and analyzed from large, high-quality, monodomain single crystal of α–RuCl3, a proximate Kitaev quantum spin liquid. Spectra were collected with laser polarizations parallel and perpendicular to the honeycomb plane. Pairs of nearly degenerate phonons were discovered and show either a fourfold or twofold polarization angle dependence in their Raman intensity, thereby providing evidence to definitively assign the bulk crystal point group as C2h. The low-frequency continuum that is often attributed to scattering from pairs of Majorana fermions was also examined and found to disappear when the laser excitation and scattered photon polarizations were perpendicular to the honeycomb plane. This disappearance, along with the behavior of the phonon spectrum in the same polarization configuration, strongly suggests that the scattering continuum is two-dimensional. Here, we argue that this scattering continuum originates from the Kitaev magnetic interactions that survives up to room temperature, a scale larger than the bare Kitaev exchange energy of approximately 50 K.

Research Organization:
Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
Sponsoring Organization:
USDOE Office of Science (SC), Basic Energy Sciences (BES); NSF MRSEC
Grant/Contract Number:
AC05-00OR22725; DMR-1420451
OSTI ID:
1606815
Journal Information:
Physical Review B, Vol. 100, Issue 13; ISSN 2469-9950
Publisher:
American Physical Society (APS)Copyright Statement
Country of Publication:
United States
Language:
English
Citation Metrics:
Cited by: 20 works
Citation information provided by
Web of Science

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Cited By (1)

Field-induced QCD 3 -Chern-Simons quantum criticalities in Kitaev materials journal January 2020

Figures / Tables (7)