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

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.

Understanding the three-dimensional quantum Hall effect in generic multi-Weyl semimetals

“…However, the experimental discovery of mWSMs is yet to be made. Now, turning our attention to the intriguing linear responses, the electric-, thermal-, magnetotransport properties have been theoretically studied for single WSM [28][29][30][31][32][33] as well as mWSMs [34][35][36][37][38][39][40] following semi-classical Boltzmann transport formalism. Meanwhile, Kubo theory is employed to study the optical responses [41][42][43][44][45][46].…”

Effect of chirality imbalance on Hall transport of PrRhC$_2$

“…The anomalous Hall effect (AHE) is, on the other hand, a key signature of non-trivial Berry curvature (BC) of magnetic WSM in the absence of magnetic field [45][46][47] . The WSMs become testbed for investigating various nonlinear transport properties apart from the above firstorder responses [48][49][50][51][52][53] .…”