Quantum phase diagram for two-species hardcore bosons in one-dimensional optical lattices with resonantly driven Rabi frequency

Following a proposed scheme for realizing the time-periodically modulated Rabi frequency in experiments, we suggest density-dependent hoppings of two-species hardcore bosons in a one-dimensional optical lattice. Distinct from the previous work [Phys. Rev. Res. 2, 013275 (2020)], we study effects in the first resonance region. In the effective Hamiltonian, the intraspecies hopping occurs only if the density discrepancy of the other species on these sites is zero, while the interspecies one is allowed once the relevant density discrepancy becomes nonzero. At integer-1 filling, the quantum phase diagram of the effective Hamiltonian is determined by the perturbation analysis together with numerical calculations. We find that in the limit of dominant J1, the system becomes a double-degenerate dimerized state spontaneously breaking the translation symmetry. The interplay of J0, J1, and the fixed U?? = 1 leads to three BKT transition lines and a tricritical BKT point. Exact transition lines are obtained by the level spectroscopic technique. Besides, general physical properties, including the charge gap, neutral gap, superfluid density, and dimerization strength, are investigated as well.

Automated summary

In this study, density-dependent hoppings of two-species hardcore bosons in a one-dimensional optical lattice were investigated, focusing on the effects in the first resonance region. The system undergoes a phase transition and exhibits a state that breaks the translation symmetry. The level spectroscopic technique was used to obtain precise transition lines, and other physical properties were also examined.