1. Majorana-fermion origin of the planar thermal Hall effect in the Kitaev magnet $\alpha$-RuCl$_3$
- Author
-
Imamura, K., Suetsugu, S., Mizukami, Y., Yoshida, Y., Hashimoto, K., Ohtsuka, K., Kasahara, Y., Kurita, N., Tanaka, H., Noh, P., Nasu, J., Moon, E. -G., Matsuda, Y., and Shibauchi, T.
- Subjects
Condensed Matter - Strongly Correlated Electrons ,Condensed Matter - Materials Science - Abstract
The field-induced quantum disordered state of layered honeycomb magnet $\alpha$-RuCl$_3$ is a prime candidate for Kitaev spin liquids hosting Majorana fermions and non-Abelian anyons. Recent observations of anomalous planar thermal Hall effect demonstrate a topological edge mode, but whether it originates from Majorana fermions or bosonic magnons remains controversial. Here we distinguish these origins from low-temperature measurements of high-resolution specific heat and thermal Hall conductivity with rotating in-plane fields. In the honeycomb bond direction, a distinct closure of the low-energy bulk gap is observed concomitantly with the sign reversal of the Hall effect. General discussions of topological bands show that this is the hallmark of an angle-rotation-induced topological transition of fermions, providing conclusive evidence for the Majorana-fermion origin of the thermal Hall effect in $\alpha$-RuCl$_3$., Comment: 21 pages, 7 figures
- Published
- 2023
- Full Text
- View/download PDF