Butterfly-like anisotropic magnetoresistance and angle-dependent Berry phase in Type-II Weyl semimetal WP2

TL;DR

This study explores the anisotropic magnetoresistance and angle-dependent Berry phase in the type-II Weyl semimetal WP2, revealing its topological features and Fermi surface anisotropy with potential device applications.

Contribution

It provides a comprehensive experimental analysis of WP2's topological properties, including butterfly-like magnetoresistance and angle-dependent Berry phase, highlighting its novel physical characteristics.

Findings

Butterfly-like magnetoresistance at low temperature

Evolution of magnetoresistance from four-lobed to two-lobed with temperature

Angle-dependent Berry phase linked to topological singularities

Abstract

Weyl semimetal emerges as a new topologically nontrivial phase of matter, hosting low-energy excitations of massless Weyl fermions. Here, we present a comprehensive study of the type-II Weyl semimetal WP2. Transport studies show a butterfly-like magnetoresistance at low temperature, reflecting the anisotropy of the electron Fermi surfaces. The four-lobed feature gradually evolves into a two-lobed one upon increasing temperature, mainly due to the reduced relative contribution of electron Fermi surfaces compared to hole Fermi surfaces for the magnetoresistance. Moreover, angle-dependent Berry phase is further discovered from the quantum oscillations, which is ascribed to the effective manipulation of the extremal Fermi orbits by the magnetic field to feel the nearby topological singularities in the momentum space. The revealed topological characters and anisotropic Fermi surfaces of WP2 substantially enrich the physical properties of Weyl semimetals and hold great promises in topological electronic and Fermitronic device applications.