Distinct signatures of particle-hole symmetry breaking in transport coefficients for generic multi-Weyl semimetals

TL;DR

This paper investigates how particle-hole symmetry breaking in multi-Weyl semimetals affects transport phenomena like CPGE, BCD, and MHE, revealing distinct signatures for different phases and providing experimental probes.

Contribution

It introduces generic lattice models for multi-Weyl semimetals with broken particle-hole symmetry and analyzes their unique transport signatures across various phases.

Findings

Quantized CPGE response in hybrid mWSM phase for model I

Distinct frequency profiles of CPGE in different phases

Characteristic BCD and MHE signatures for phase differentiation

Abstract

We propose and study generic multi-Weyl semimetal (mWSM) lattice Hamiltonians that break particle-hole symmetry. These models fall into two categories: model I (model II) where the gap and tilt terms are coupled (decoupled) can host type-I and type-II Weyl nodes simultaneously (separately) in a hybrid phase (type-I and type-II phases, respectively). We concentrate on the question of how anisotropy and non-linearity in the dispersions, gaps and tilt terms influence diffusive second order transport quantities namely, the circular photogalvanic effect (CPGE) and the Berry curvature dipole (BCD) as well as first order Magnus Hall effect (MHE) in the ballistic limit. The signatures of topological charges are clearly imprinted in the quantized CPGE response for the hybrid mWSM phase in model I. Such a quantization is also found in the type-I WSM phase for model II, however, the frequency profiles of the CPGE in these two cases is distinctively different owing to their different band dispersion irrespective of the identical topological properties. The contributions from the vicinity of Weyl nodes and away from the WNs are clearly manifested in the BCD response, respectively, for model I model II. The Fermi surface properties for the activated momentum lead to a few hallmark features on the MHE for both the models. Furthermore, we identify distinguishing signatures of the above responses for type-I, type-II and hybrid phases to provide an experimentally viable probe to differentiate these WSMs phases.