Landau–Zener tunneling in spin–orbit-coupled Bose–Einstein condensates in [formula omitted] periodic potentials

Abstract

We study Landau–Zener (LZ) transition probability between Bloch bands in Bose–Einstein condensates (BECs) with parity-time (PT)-symmetric periodic potentials. The roles of the Raman coupling, the energy detuning, the spin–orbit coupling (SOC) and PT potentials are investigated for the corresponding transition. We find that the imaginary part of PT potentials plays important roles in the LZ tunneling rates when the chemical potentials are less than the exceptional points. We also find that the transition probabilities of the higher Bloch band gaps are usually larger than the lower band gaps, except that the initial stage of the eigen energy degeneracy is broken in ground state.