We have developed a new scheme for tunable optical lattices that can switch, ramp or modulate between a honeycomb, boron-nitride and triangular lattice. We use it to prepare higher bands and to introduce a sublattice-modulation spectroscopy. Furthermore, we introduce the geometry phase as a new...

In a collaboration with the theory group of Ludwig Mathey, we have observed and explained surprising density-wave patterns, which form in BECs in strongly tilted triangular optical lattices and sponteously break the discrete symmetry of the lattice.

H. P. Zahn, V. P. Singh, M. N. Kosch, L. Asteria...