%0 Journal Article
%T Edge States: Topological Insulators, Superconductors and QCD Chiral Bags
%A M. Asorey
%A A. P. Balachandran
%A J. M. Perez-Pardo
%J Physics
%D 2013
%I arXiv
%R 10.1007/JHEP12(2013)073
%X The dynamics of the magnetic field in a superconducting phase is described by an effective massive bosonic field theory. If the superconductor is confined in a domain M with boundary \partial M, the boundary conditions of the electromagnetic fields are predetermined by physics. They are time-reversal and also parity invariant for adapted geometry. They lead to edge excitations while in comparison, the bulk energies have a large gap. A similar phenomenon occurs for topological insulators where appropriate boundary conditions for the Dirac Hamiltonian also lead to similar edge states and an 'incompressible bulk'. They give spin-momentum locking as well. In addition time-reversal and parity invariance emerge for adapted geometry. Similar edge states appear in QCD bag models with chiral boundary conditions.
%U http://arxiv.org/abs/1308.5635v3