摘要
We investigate the mean-field energy spectrum and dynamics in a Bose–Einstein condensate in a double-well potential with non-Hermiticity from the nonreciprocal hopping,and show that the interplay of nonreciprocity and nonlinearity leads to exotic properties.Under the two-mode and mean-field approximations,the nonreciprocal generalization of the nonlinear Schrödinger equation and Bloch equations of motion for this system are obtained.We analyze the PT phase diagram and the dynamical stability of fixed points.The reentrance of PT-symmetric phase and the reformation of stable fixed points with increasing the nonreciprocity parameter are found.Besides,we uncover a linear selftrapping effect induced by the nonreciprocity.In the nonlinear case,the self-trapping oscillation is enhanced by the nonreciprocity and then collapses in the PT-broken phase,and can finally be recovered in the reentrant PT-symmetric phase.
基金
supported by the National Natural Science Foundation of China(Grant Nos.12174126,12104166,U1830111,11947097,and 12047522)
the Key-Area Research and Development Program of Guangdong Province(Grant No.2019B030330001)
the Science and Technology of Guangzhou(Grant No.2019050001),and the Guangdong Basic and Applied Basic Research Foundation(Grant Nos.2020A1515110290 and 2021A1515010315).
