Unusual magnetoresistance oscillations in preferentially oriented p-type polycrystalline ZrTe5

TL;DR

This study reports the observation of magnetoresistance oscillations in high-quality p-type ZrTe5 polycrystals that are periodic in magnetic field, revealing topological surface states and Weyl semimetal-like behavior, contrasting previous findings.

Contribution

The paper demonstrates magnetoresistance oscillations periodic in magnetic field in p-type ZrTe5, highlighting topological surface states and Weyl semimetal characteristics in polycrystalline samples.

Findings

Magnetoresistance oscillations are periodic in B, not in log B.

High mobility and small effective mass observed.

Evidence of topological surface states and Weyl semimetal behavior.

Abstract

Recently H. Wang et al. (arXiv 1704.00995) have reported quantum oscillation in magnetoresistance with the periodicity in logarithmic of magnetic field (B) for the p-type ZrTe5. They have ascribed this type of behavior to the discrete scale invariance, resulting from Effimov bound states. We have prepared high quality stoichiometric (p-type) ZrTe5 polycrystals and observed magnetoresistance (MR) oscillations, which are periodic in B. These oscillations are in contrast to usual SdH oscillations or log B dependent oscillations as observed for tellurium deficient and stoichiometric ZrTe5 respectively. The MR follows the three dimensional Weyl semimetal like behavior, and Kohler's rule is obeyed at low temperatures. We obtained small cyclotron effective mass (m* = 0.05 m_e), very high mobility of 2.2 X 10^4 cm^2/V.s and the signature of topological protected surface states in the compound. The magnetic data shows zero cusp paramagnetic susceptibility which supports the existence of topological surface states in ZrTe5.