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arXiv · 2305.03400

Chiral excitations and the intermediate-field spin-liquid regime in the Kitaev magnet $\alpha$-RuCl$_3$

Anuja Sahasrabudhe·Mikhail A. Prosnikov·Thomas C. Koethe·Philipp Stein·Vladimir Tsurkan·Alois Loidl·Markus Grüninger·Hamoon Hedayat·Paul H. M. van Loosdrecht
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Abstract

In the Kitaev magnet $\alpha$-RuCl$_3$, the existence of a magnetic-field-induced quantum spin liquid phase and of anyonic excitations are discussed controversially. We address this elusive, exotic phase via helicity-dependent Raman scattering and analyze the Raman optical activity of excitations as a function of magnetic field and temperature. The hotly debated field regime between 7.5 T and 10.5 T is characterized by clear spectroscopic signatures such as a plateau of the Raman optical activity of the dominant, chiral spin-flip excitation. This provides direct evidence for the existence of a distinct intermediate field regime compatible with a quantum spin liquid phase.

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Anuja Sahasrabudhe, Mikhail A. Prosnikov, Thomas C. Koethe, Philipp Stein, Vladimir Tsurkan, Alois Loidl, Markus Grüninger, Hamoon Hedayat, Paul H. M. van Loosdrecht. 2023-05-05. Chiral excitations and the intermediate-field spin-liquid regime in the Kitaev magnet $\alpha$-RuCl$_3$. https://doi.org/10.1103/physrevresearch.6.l022005

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