Evidence for Layered Quantized Transport in Dirac Semimetal ZrTe5

Abstract

ZrTe₅ is an important semiconductor thermoelectric material and a candidate topological insulator. Here we report the observation of Shubnikov-de Hass (SdH) oscillations accompanied by quantized Hall resistance in bulk ZrTe₅ crystal, with a mobility of 41,000 cm²V^-1s^-1. We have found that the quantum oscillations does not originate from the surface states, but from the bulk states. Each single layer ZrTe₅ acted like an independent 2D electron system in the quantum Hall regime having the same carrier density and mobilities, while the bulk of the sample exhibits a multilayered quantum Hall effect.