Anomalous hysteretic behavior in a system of dipolar Bose gases

We investigate the hysteresis characteristics in a system of dipolar Bose gases loaded into a triangular lattice. We perform a large-size cluster mean-field analysis for the corresponding dipolar Bose-Hubbard model in the hard-core boson limit, and show that in varying the chemical potential the system can exhibit a hysteretic behavior without forming the standard "hysteresis-loop" structure. In this anomalous hysteresis, the quantum melting transition from the supersolid (or solid) to superfluid state can occur, but the reverse process (quantum solidification) is impossible.