Alexander Szameit, Mikael C. Rechtsman, Omri Bahat-Treidel, Mordechai Segev
We apply gain/loss to honeycomb photonic lattices and demonstrate that optical tachyons, a photonic version of particles that travel faster than the speed of light, can be generated by PT-symmetry breaking in this structure. We further show that the PT-symmetry can be restored via strain.
http://arxiv.org/abs/1103.3389
Optics (physics.optics)