Chirality represents a kind of symmetry breaking characterized by the noncoincidence of an object with its mirror image and has been attracting intense attention in a broad range of scientific areas. The recent realization of spin-orbit coupling in u
ltracold atomic gases provides a new perspective to study quantum states with chirality. In this Letter, we demonstrate that the combined effects of spin-orbit coupling and interatomic soft-core long-range interaction can induce an exotic supersolid phase in which the chiral symmetry is broken with spontaneous emergence of circulating particle current. This implies that a finite angular momentum can be generated with neither rotation nor effective magnetic field. The direction of the angular momentum can be altered by adjusting the strength of spin-orbit coupling or interatomic interaction. The predicted chiral supersolid phase can be experimentally observed in Rydberg-dressed Bose-Einstein condensates with spin-orbit coupling.
We study a quasispin-$1/2$ Bose-Einstein condensate with synthetically generated spin-orbit coupling in a toroidal trap, and show that the system has a rich variety of ground and metastable states. As the central hole region increases, i.e., the pote
ntial changes from harmonic-like to ring-like, the condensate exhibits a variety of structures, such as triangular stripes, flower-petal patterns, and counter-circling states. We also show that the rotating systems have exotic vortex configurations. In the limit of a quasi-one dimensional ring, the quantum many-body ground state is obtained, which is found to be the fragmented condensate.
We consider a spin-1 Bose-Einstein condensate with Rashba spin-orbit coupling and dipole-dipole interaction confined in a cigar-shaped trap. Due to the combined effects of spin-orbit coupling, dipole-dipole interaction, and trap geometry, the system
exhibits a rich variety of ground-state spin structures, including twisted spin vortices. The ground-state phase diagram is determined with respect to the strengths of the spin-orbit coupling and dipole-dipole interaction.
We show that double-quantum spin vortices, which are characterized by doubly quantized circulating spin currents and unmagnetized filled cores, can exist in the ground states of SU(3) spin-orbit coupled Bose gases. It is found that the SU(3) spin-orb
it coupling and spin-exchange interaction play important roles in determining the ground-state phase diagram. In the case of effective ferromagnetic spin interaction, the SU(3) spin-orbit coupling induces a three-fold degeneracy to the magnetized ground state, while in the antiferromagnetic spin interaction case, the SU(3) spin-orbit coupling breaks the ordinary phase rule of spinor Bose gases, and allows the spontaneous emergence of double-quantum spin vortices. This exotic topological defect is in stark contrast to the singly quantized spin vortices observed in existing experiments, and can be readily observed by the current magnetization-sensitive phase-contrast imaging technique.
We investigate the dynamics and modulation of ring dark soliton in 2D Bose-Einstein condensates with tunable interaction both analytically and numerically. The analytic solutions of ring dark soliton are derived by using a new transformation method.
For shallow ring dark soliton, it is stable when the ring is slightly distorted, while for large deformation of the ring, vortex pairs appear and they demonstrate novel dynamical behaviors: the vortex pairs will transform into dark lumplike solitons and revert to ring dark soliton periodically. Moreover, our results show that the dynamical evolution of the ring dark soliton can be dramatically affected by Feshbach resonance, and the lifetime of the ring dark soliton can be largely extended which offers a useful method for observing the ring dark soliton in future experiments.
