Second-harmonic voltage responce for the magnetic Weyl semimetal Co3Sn2S2
V. D. Esin, A. V. Timonina, N. N. Kolesnikov, E. V. Deviatov
Institute of Solid State Physics of the Russian Academy of Sciences, 142432 Chernogolovka, Russia
Abstract
We experimentally investigate longitudinal and transverse second-harmonic
voltage response to ac electrical current for a magnetic Weyl semimetal
Co3Sn2S2. In contrast to the previously observed Berry-curvature
induced non-linear Hall effect for non-magnetic Weyl and Dirac semimetals, the
second-harmonic transverse voltage demonstrates sophisticated interplay of
different effects for Co3Sn2S2. In high magnetic fields, it is of
Seebeck-like square-B law, while the low-field behavior is found to be linear
and sensitive to the direction of sample magnetization. The latter can be
expected both for the non-linear Hall effect and for the surface state
contribution to the Seebeck effect in Weyl semimetals. Thus, thermoelectric
effects are significant in Co3Sn2S2, unlike non-magnetic Weyl and
Dirac materials.