Effects of surface potentials on Goos-Hänchen and Imbert-Fedorov shifts in Weyl semimetals

Abstract

Weyl semimetals exhibit a myriad of exotic transport responses, among which, the Goos-H\"anchen (GH) and Imbert-Fedorov (IF) effects have recently garnered substantial attention. Besides the usual parametric dependence inherited from the underlying Hamiltonian to describe a Weyl system, the IF shift particularly carries a topological identity---it depends on the chirality of the Weyl cones. Observing such signatures following the trail of theoretical predictions applied to clean systems can be severely obfuscated by surface potentials induced by localized impurities that are naturally present in real materials hosting the semimetallic phase. Classifying these potentials, we study their effects on GH and IF shifts to provide useful guidance to experiments that are tuned to the objective of characterizing Weyl semimetals and leveraging them to provide the basis for future technological advances. A transfer matrix-based approach is proposed to study the profile of Weyl wave functions scattering from the impurity potentials. As we unfold, the presence of such potentials can lead to several remarkable effects such as the complete nullification of the IF shift and valley inversion.