Laboratoire de Physique Théorique
Toulouse - UMR 5152

M. Piraud, F. Heidrich-Meisner, I. P. McCulloch, S. Greschner, T. Vekua and U. Schollwöck

In this talk I will present the phase diagram of the strongly-interacting Bose-Hubbard model defined on a two-leg ladder geometry in the presence of a homogeneous flux. Our work was motivated by a recent experiment [Atala et al., Nature Phys. \bf 10, 588 (2014)], which studied the same system, in the complementary regime of weak interactions. Based on extensive density matrix renormalization group simulations and a bosonization analysis, we have fully explored the parameter space spanned by filling, inter-leg tunneling, and flux. As a main result, we demonstrate the existence of gapless and gapped Meissner and vortex phases, with the gapped states emerging in Mott-insulating regimes. We calculate experimentally accessible observables such as chiral currents and vortex patterns and study their dependence on model parameters.