Coherent transport of cold atoms in angle-tuned optical lattices

Optical lattices with a large spacing between the minima of the optical potential can be created using the angle-tuned geometry where the one-dimensional periodic potential is generated by two propagating laser beams intersecting at an angle different from pi. The present work analyzes the coherent transport for the case of this geometry. We show that the potential depth can be kept constant during the transport by choosing a magic value for the laser wavelength. This value agrees with that of the counterpropagating laser case, and the magic wavelength does not depend on the optical lattice geometry. Moreover, we find that this scheme can be used to implement controlled collision experiments under special geometric conditions. Finally we study the transport of hyperfine-Zeeman states of (87)Rb.