PT-symmetry in honeycomb photonic lattices
arXiv:1103.3389 · doi:10.1103/PhysRevA.84.021806
Abstract
We apply gain/loss to honeycomb photonic lattices and show that the dispersion relation is identical to tachyons - particles with imaginary mass that travel faster than the speed of light. This is accompanied by PT-symmetry breaking in this structure. We further show that the PT-symmetry can be restored by deforming the lattice.