Pi Berry phase and Zeeman splitting of TaP probed by high field magnetotransport measurements

TL;DR

This study investigates the topological Weyl semimetal TaP using high-field magnetotransport measurements, revealing its Berry phase, Zeeman splitting, and key transport properties indicative of Weyl fermions.

Contribution

It provides the first detailed analysis of TaP's quantum transport properties, including Berry phase, Zeeman splitting, and generalized Lifshitz-Kosevich formula application.

Findings

TaP exhibits signatures of Weyl fermions, including negative magnetoresistance and light effective masses.

Non-trivial Berry phase of Pi was confirmed for multiple Fermi pockets.

Zeeman splitting was observed, allowing extraction of the Landé g-factor.

Abstract

The chiral anomaly-induced negative magnetoresistance and non-trivial Berry phase are two fundamental transport properties associated with the topological properties of Weyl fermions. In this work, we report the quantum transport of TaP single crystals in magnetic field up to 31T. Through the analyses of our magnetotransport data, we show TaP has the signatures of a Weyl state, including light effective quasiparticle masses, ultrahigh carrier mobility, as well as negative longitudinal magnetoresistance. Furthermore, we have generalized the Lifshitz-Kosevich formula for Shubnikov-de Haas (SdH) oscillations with multi-frequencies, and determined the non-trivial Berry phase of Pi for multiple Fermi pockets in TaP through the direct fitting of the quantum oscillations. In high fields, we also probed signatures of Zeeman splitting, from which the Land\'e g-factor is extracted.