Anomalous plasmon mode in strained Weyl semimetals

TL;DR

This paper predicts a novel anomalous plasmon mode in strained Weyl semimetals, arising from topological effects and quasiparticle interactions, with unique dispersion and thermal properties, potentially observable via THz vibrations.

Contribution

It introduces a new anomalous plasmon mode in strained Weyl semimetals based on topological Landau Fermi liquid and chiral kinetic theories, highlighting its unique dispersion and experimental detection.

Findings

Identifies a gapped collective mode from charge pumping between bulk and surface.

Shows the mode disperses unidirectionally along pseudomagnetic fields.

Predicts unusual thermal conductivity violating Wiedemann-Franz law.

Abstract

An exotic anomalous plasmon mode is found in strained Weyl semimetals utilizing the topological Landau Fermi liquid and chiral kinetic theories, in which quasiparticle interactions are modeled by long-range Coulomb and residual short-range interactions. The gapped collective mode is derived from the dynamical charge pumping between the bulk and the surface and behaves like $k_{\rm F}^{-1}$. The charge oscillations are accurately determined by the coupling between the induced electric field and the background pseudofields. This novel mode unidirectionally disperses along the pseudomagnetic field and manifests itself in an unusual thermal conductivity in apparent violation of the Wiedemann-Franz law. The excitation can be achieved experimentally by mechanical vibrations of the crystal lattice in the THz regime.