Manipulation of double-well tunneling in BEC based on a movable Gaussian-type potential barrier

Double-well potentials are important potential models that underlie the study of macroscopic quantum tunneling in Bose-Einstein Condensates (BECs), which are most commonly constructed in the form of a combination of a finite square-well potential and a square potential barrier. We propose another possibility of constructing a double-well potential, which consists of the combination of a square-well potential and a movable Gaussian-type potential barrier, and by adjusting the width, height, symmetry, and position of the movable potential barrier, symmetric and asymmetric double-well potentials with rich structures can be constructed. By numerically solving the Gross-Pitaevskii equation (GPE), we give the ground state structures of the BEC in this double-well potential, and then study the tunneling dynamics in the BEC in this double-well potential. The results show that the parameters of the movable potential can control the ground state structure and tunneling dynamics of the BEC system very precisely, and the ground state structure and tunneling dynamics are more sensitive to the asymmetric Gaussian-type potential barrier.