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arXiv · 1904.05609

Pressure-tuning of the electrical-transport properties in the Weyl semimetal TaP

M. Besser·R. D. dos Reis·F. -R. Fan·M. O. Ajeesh·Y. Sun·M. Schmidt·C. Felser·M. Nicklas
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Abstract

We investigated the pressure evolution of the electrical transport in the almost compensated Weyl semimetal TaP. In addition, we obtained information on the modifications of the Fermi-surface topology with pressure from the analysis of pronounced Shubnikov-de Haas (SdH) quantum oscillations present in the Hall-effect and magnetoresistance data. The simultaneous analysis of the Hall and longitudinal conductivity data in a two-band model revealed an only weak decrease in the electron- and hole charge-carrier densities up to 1.2 GPa, while the mobilities are essentially pressure independent along the a-direction of the tetragonal crystal structure. Only weak changes in the SdH frequencies for B||a and B||c point at a robust Fermi-surface topology. In contrast to the stability of the Fermi-surface topology and of the density of charge carriers, our results evidence a strong pressure variation of the magnitude of transverse magnetoresistance for B||a contrary to the results for B||c. We can relate the former to an increase in the charge-carrier mobilities along the crystallographic c-direction.

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M. Besser, R. D. dos Reis, F. -R. Fan, M. O. Ajeesh, Y. Sun, M. Schmidt, C. Felser, M. Nicklas. 2019-04-11. Pressure-tuning of the electrical-transport properties in the Weyl semimetal TaP. https://doi.org/10.1103/physrevmaterials.3.044201

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