Anomalous Thermal Conductivity and Magnetic Torque Response in the Honeycomb Magnet α-RuCl_{3}

• Published in: Physical review letters Vol. 118; no. 18; p. 187203
• Main Authors: Leahy, Ian A, Pocs, Christopher A, Siegfried, Peter E, Graf, David, Do, S-H, Choi, Kwang-Yong, Normand, B, Lee, Minhyea
• Format: Journal Article
• Language: English
• Published: United States 05.05.2017
• ISSN: 1079-7114
• DOI: 10.1103/PhysRevLett.118.187203

We report on the unusual behavior of the in-plane thermal conductivity κ and torque τ response in the Kitaev-Heisenberg material α-RuCl_{3}. κ shows a striking enhancement with linear growth beyond H=7  T, where magnetic order disappears, while τ for both of the in-plane symmetry directions shows an anomaly at the same field. The temperature and field dependence of κ are far more complex than conventional phonon and magnon contributions, and require us to invoke the presence of unconventional spin excitations whose properties are characteristic of a field-induced spin-liquid phase related to the enigmatic physics of the Kitaev model in an applied magnetic field.