Bistable multipole quantum droplets in binary Bose-Einstein condensates
Liangwei Dong, Dongshuai Liu, Zhijing Du, Kai Shi, Qi Wei
Abstract
We address the existence and stability of multipole quantum droplets in symmetric binary Bose-Einstein condensates described by the amended Gross-Pitaevskii equation with Lee-Huang-Yang quantum corrections. Quantum droplets trapped in a weakly anharmonic potential can be composed of different numbers of globally linked poles with an azimuthally periodic distribution. Due to the competing Lee-Huang-Yang-augmented nonlinearity, the norm of two branches of droplets with slopes of opposite sign merges together at a lower cutoff of chemical potential. The lower and upper branches of droplets at the same chemical potential, but with a different norm, can evolve stably in certain parameter regions simultaneously. The stability domain of droplets shrinks with the growth of the number of poles. Even unstable necklacelike droplets can survive for a very long time.