We investigate the fragmentatiion in a two-mode Bose-Einstein condensate with Josephson cou- pling. We explore how the fragmentation and entropy of the ground state depend on the intermode asymmetry and interparticle ...We investigate the fragmentatiion in a two-mode Bose-Einstein condensate with Josephson cou- pling. We explore how the fragmentation and entropy of the ground state depend on the intermode asymmetry and interparticle interactions. Owing to the interplay between the asymmetry and the interactions, a sequence of notches and plateatus in the fragraentution appears with the single-atom tunneling and interaction blockade, respectively. We then analyze the dynamical properties of the fragmentation in three typical quenches of the asymmetry: linear, sudden, and periodic quenches. In a linear quench, the final sta,~e is a fragmented state due to the sequential Landau-Zener tunnel- ing, which can be analytically explained by applying the two-level Landau-Zener formula for each avoided level crossing. In a sudden quench, the fragmentation exhibits persistent fluctuations that sensitively depend on the interparticle interactions and interrnode coupling. In a periodic quench, the fragmentation is modulated: by the periodic driving, and a suitable modulation may allow one to control the fragmentation.展开更多
文摘We investigate the fragmentatiion in a two-mode Bose-Einstein condensate with Josephson cou- pling. We explore how the fragmentation and entropy of the ground state depend on the intermode asymmetry and interparticle interactions. Owing to the interplay between the asymmetry and the interactions, a sequence of notches and plateatus in the fragraentution appears with the single-atom tunneling and interaction blockade, respectively. We then analyze the dynamical properties of the fragmentation in three typical quenches of the asymmetry: linear, sudden, and periodic quenches. In a linear quench, the final sta,~e is a fragmented state due to the sequential Landau-Zener tunnel- ing, which can be analytically explained by applying the two-level Landau-Zener formula for each avoided level crossing. In a sudden quench, the fragmentation exhibits persistent fluctuations that sensitively depend on the interparticle interactions and interrnode coupling. In a periodic quench, the fragmentation is modulated: by the periodic driving, and a suitable modulation may allow one to control the fragmentation.