English

Supersymmetric Runge-Lenz-Pauli vector for Dirac vortex in topological insulators and graphene

Mesoscale and Nanoscale Physics 2011-06-23 v2 Superconductivity High Energy Physics - Theory

Abstract

The Dirac mass-vortex at the surface of a topological insulator or in graphene is considered. Within the linear approximation for the vortex amplitude's radial dependence, the spectrum is a series of degenerate bound states, which can be classified by a set of accidental SU(2) and supersymmetry generators (I. F. Herbut and C.-K. Lu, Phys. Rev. B 83 125412 (2011)). Here we discuss further the properties and manifestations of the supersymmetry of the vortex Hamiltonian, and point out some interesting analogies to the Runge-Lenz-Pauli vector in the non-relativistic hydrogen atom. Symmetry breaking effects due to a finite chemical potential, and the Zeeman field are also analyzed. We find that a residual accidental degeneracy remains only in the special case of equal magnitudes of both terms, whereas otherwise it becomes removed entirely.

Keywords

Cite

@article{arxiv.1102.5163,
  title  = {Supersymmetric Runge-Lenz-Pauli vector for Dirac vortex in topological insulators and graphene},
  author = {Chi-Ken Lu and Igor F. Herbut},
  journal= {arXiv preprint arXiv:1102.5163},
  year   = {2011}
}

Comments

revised version with added reference and a new paragraph on interpretation of two-velocity Weyl fermions realized in 2D optical lattice; to appear in J Phys A