Weak Anti-Localization Effect in Topological Ni$_3$In$_2$S$_2$ Single Crystal

Abstract

Ni$_3$In$_2$S$_2$ is the most recent entrant into the family of topological insulator (TI) materials, the same exhibits very high MR in a low-temperature regime. Here, we report the crystal growth, the structural, micro-structural, and magneto-transport study of Ni$_3$In$_2$S$_2$ down to 2.5K under an applied field of up to 14Tesla. The phase purity and growth direction of a single crystal is studied by performing XRD on both powder and flake and further Rietveld analysis is also carried out. The electrical transport measurements are studied and the grown crystal showed metallic behaviour down to 2.5K, with an R300K/R2K ratio of around 7. A significant variation in magnetoresistance (MR) values is observed as the temperature is increased from 2.5K to 200K under an applied field of up to 14 Tesla. Interestingly the low T (2.5K), MR shows a clear V-type characteristic TI cusp. Magnetoconductivity data at low fields (1Tesla) is fitted with the Hikami Larkin Nagaoka (HLN) model, which showed the presence of a weak anti-localization effect in the synthesized Ni$_3$In$_2$S$_2$ crystal at low temperatures. We have successfully grown near single-phase Ni$_3$In$_2$S$_2$ and its TI behavior is demonstrated by magneto-transport measurements.