Quantum Oscillations of the Positive Longitudinal Magnetoconductivity: A Fingerprint for Identifying Weyl Semimetals

Ming-Xun Deng, G. Y. Qi, R. Ma, R. Shen, Rui-Qiang Wang, L. Sheng, and D. Y. Xing

Phys. Rev. Lett. 122, 036601 – Published 24 January 2019

Abstract

Weyl semimetals (WSMs) host charged Weyl fermions as emergent quasiparticles. We develop a unified analytical theory for the anomalous positive longitudinal magnetoconductivity (LMC) in a WSM, which bridges the gap between the classical and ultraquantum approaches. More interestingly, the LMC is found to exhibit periodic-in- $1 / B$ quantum oscillations, originating from the oscillations of the nonequilibrium chiral chemical potential. The quantum oscillations, superposed on the positive LMC, are a remarkable fingerprint of a WSM phase with a chiral anomaly, whose observation is a valid criteria for identifying a WSM material. In fact, such quantum oscillations were already observed by several experiments.

Received 15 August 2018
Revised 6 November 2018

DOI:https://doi.org/10.1103/PhysRevLett.122.036601

Physics Subject Headings (PhySH)

Magnetoresistance

Weyl semimetal

Boltzmann theory

Condensed Matter, Materials & Applied Physics

Authors & Affiliations

Ming-Xun Deng^1,2, G. Y. Qi¹, R. Ma³, R. Shen^1,4, Rui-Qiang Wang², L. Sheng^1,4,*, and D. Y. Xing^1,4,†

¹National Laboratory of Solid State Microstructures and Department of Physics, Nanjing University, Nanjing 210093, China
²Laboratory of Quantum Engineering and Quantum Materials, ICMP and SPTE, South China Normal University, Guangzhou 510006, China
³Jiangsu Key Laboratory for Optoelectronic Detection of Atmosphere and Ocean, Nanjing University of Information Science and Technology, Nanjing 210044, China
⁴Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China