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arXiv · 1703.08474

Gapless Spin Excitations in the Field-Induced Quantum Spin Liquid Phase of alpha-RuCl3

Jiacheng Zheng·Kejing Ran·Tianrun Li·Jinghui Wang·Pengshuai Wang·Bin Liu·Zhengxin Liu·B. Normand·Jinsheng Wen·Weiqiang Yu
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Abstract

$α$-RuCl$_3$ is a leading candidate material for theobservation of physics related to the Kitaev quantum spin liquid (QSL). By combined susceptibility, specific-heat, and nuclear-magnetic-resonance measurements, we demonstrate that $α$-RuCl$_3$ undergoes a quantum phase transition to a QSL in a magnetic field of 7.5 T applied in the $ab$ plane. We show further that this high-field QSL phase has gapless spin excitations over a field range up to 16 T. This highly unconventional result, unknown in either Heisenberg or Kitaev magnets, offers insight essential to establishing the physics of $α$-RuCl$_3$.

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Jiacheng Zheng, Kejing Ran, Tianrun Li, Jinghui Wang, Pengshuai Wang, Bin Liu, Zhengxin Liu, B. Normand, Jinsheng Wen, Weiqiang Yu. 2017-12-11. Gapless Spin Excitations in the Field-Induced Quantum Spin Liquid Phase of alpha-RuCl3. https://doi.org/10.1103/physrevlett.119.227208

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