Magnetoresistance and Kohler rule in the topological chiral semimetals CoSi

TL;DR

This study investigates the magnetoresistance behavior of CoSi, a topological chiral semimetal, confirming the applicability of the Kohler rule at low fields and observing quantum oscillations, with deviations at high fields indicating complex electronic properties.

Contribution

It provides new insights into the magnetoresistance and quantum oscillations in CoSi, highlighting the conditions under which the Kohler rule holds and deviations occur.

Findings

Kohler rule applies to transverse MR in CoSi.

Kohler rule is valid for longitudinal MR at low magnetic fields.

High magnetic fields cause deviation and sign change in longitudinal MR.

Abstract

The transverse and longitudinal magnetoresistance (MR) of two samples of the topological chiral semimetal CoSi with different RRR was studied. It is shown that the Kohler rule works for the transverse MR. The Kohler rule is also fulfilled in the case of longitudinal MR at a low reduced magnetic field. A sharp deviation of longitudinal MR curve for sample with low RRR from the Kohler prediction at high fields reveals its tendency to a sign change at higher magnetic fields. The Shubnikov de Haas quantum oscillations were observed and analyzed in both perpendicular and parallel configurations of the current and magnetic field in sample CoSi 1 with RRR 9.33 at low temperatures.