Effective Dirac dynamics of ultracold atoms in bichromatic optical lattices
Dirk Witthaut, Tobias Salger, Sebastian Kling +2 more
We study the dynamics of ultracold atoms in tailored bichromatic optical lattices. By tuning the lattice parameters, one can readily engineer the band structure and realize a Dirac point, i.e., a true crossing of two Bloch bands. The dynamics in the vicinity of such a crossing is described by the one-dimensional Dirac equation, which is rigorously shown beyond the tight-binding approximation. Within this framework we analyze the effects of an external potential and demonstrate numerically that it is possible to demonstrate Klein tunneling with current experimental setups.
arXiv:1102.4047•Physical Review A•Sep 1, 2011•47 citations