Polarization in quasirelativistic graphene model with topologically non-trivial charge carriers

TL;DR

This paper models graphene's electronic properties using a high-energy Hamiltonian approach, revealing topologically non-trivial charge carriers and polarization effects, with implications for understanding non-Abelian excitations and conductivity.

Contribution

It introduces a quasi-relativistic graphene model with Majorana-like modes, analyzing topological charge structures and polarization effects not previously explored.

Findings

Zak-phases form a cyclic group Z12 deformed to Z8 at high momenta

Simulations show complex conductivity influenced by spatial dispersion

Polarization exhibits spatial periodicity in models with Majorana-like carriers

Abstract

Within the earlier developed high-energy-$\vec k\cdot \vec p$-Hamiltonian approach to describe graphene-like materials, the simulations of band structure, non-Abelian Zak phases and complex conductivity of graphene have been performed. The quasi-relativistic graphene model with a number of flavors (gauge fields) $N_F=3$ in two approximations (with and without a pseudo-Majorana mass term) has been utilized as a ground for the simulations. It has been shown that a Zak-phases set for the non-Abelian Majorana-like excitations (modes) in graphene is the cyclic group $\mathbf{Z}_{12}$ and this group is deformed into a smaller one $\mathbf{Z}_8$ at sufficiently high momenta due to a deconfinement of the modes. Simulations of complex longitudinal low-frequency conductivity have been performed with focus on effects of spatial dispersion. The spatial periodic polarization in the graphene models with the pseudo Majorana charge carriers is offered.