Fermi surface evolution in Weyl semimetal t-PtBi$_2$ probed by transverse transport properties

Abstract

The combination of non-trivial topology and superconductivity opens to novel quantum devices. The discovery of intrinsic materials where such properties appear together represents a frontier in modern condensed matter physics. Trigonal PtBi$_2$ has recently emerged as a possible candidate, being the first example of superconducting type-I Weyl semimetal. However, several aspects of this promising compound still need to be unveiled, concerning its complicated band structure, the actual role of Weyl points in determining its electronic properties and the nature of the superconducting transition. In this work, we experimentally investigated a t-PtBi$_2$ single crystal by means of the Hall and Nernst effects. In particular, we revealed a change of regime in its electronic properties, which is compatible with a temperature and magnetic field evolution of hole-like pockets in the Fermi Surface.