Landau-Zener-Bloch oscillations and valley-dependent vortex generation in photonic graphene

摘要

We observe Bloch oscillations and Landau-Zener-tunneling at Dirac points in photonic graphene. The non-adiabatic wave dynamics depend anisotropically on the direction of an applied index gradient, resulting in imperfect Landau-Zener-tunneling and valley-dependent vortex generation.