Skin superfluid, topological Mott insulators, and asymmetric dynamics in an interacting non-Hermitian Aubry-André-Harper model
Dan-Wei Zhang, Yulian Chen, Guo-Qing Zhang, Li-Jun Lang, Zhi Li, Shi-Liang Zhu
Abstract
Non-Hermitian quantum many-body systems are a fascinating subject to be explored. Using the generalized density matrix renormalization group method and complementary exact diagonalization, we elucidate the many-body ground states and dynamics of a 1D interacting non-Hermitian Aubry-Andr\'e-Harper model for bosons. We find stable ground states in the superfluid and Mott-insulating regimes under wide range of conditions in this model. We reveal a skin superfluid state induced by the non-Hermiticity from the nonreciprocal hopping. We investigate the topology of the Mott-insulating phase and find its independence of the non-Hermiticity. The topological Mott insulators in this non-Hermitian system are characterized by four equal Chern numbers and a quantized shift of biorthogonal many-body polarizations. Furthermore, we show generic asymmetric expansion and correlation dynamics in the system.