Bose-Einstein Condensation of a Coherently Coupled Lee-Huang-Yang Gas

Che-Hsiu Hsueh, Ching-Wei Wang, W. C. Wu

We numerically investigate the vortex structures in a fast rotating two-dimensional Rydberg-dressed Bose-Einstein condensate (BEC) taking into account the Lee-Huang-Yang (LHY) quantum correction. In a rotating BEC of reduced dimensionality, it is shown that there is room to tune the LHY coupling against the short- and long-range couplings. In the absence of the LHY effect, hexagonal, square, striped, and honeycomb lattices can exhibit upon increasing the long-range interaction, which can be realized in the context of superfluid (SF)-supersolid (SS) transition. In the presence of the LHY effect, competition between LHY and long-range terms results in rich lattice structures. In particular, clustering of multiple vortices can occur due to the trapping effect of the SS triangles or grids. Estimates of number of vortices in the clustering are provided.

Carl Wieman

C. G. Townsend, N. J. van Druten, Michael R. Andrews +4 more

Haibin Tang, Ning Yue, Jiang-Peng Yao +4 more

The interplay of quantum fluctuation through the Lee-Huang-Yang (LHY) correction and spin-orbit coupling can modify the stability of the ultradilute Bose-Bose mixtures and result in rich nonlinear physics. Here, under the action of spin-orbit coupling, LHY correction, and rotation, the ground state and vortex excitation of spin-orbit coupled Bose-Einstein condensates (BECs) with LHY correction trapped in a rotating potential are studied. Stable isotropic and anisotropic ground states with zero momentum (in the zero-momentum phase) and nonzero momentum (in the plane wave phase) are obtained. It is shown that anisotropic ground states are persistent near the phase boundary. Particularly, unpolarized and polarized vortex states are predicted. The phase transition condition, the effective mass and quadrupole surface mode describing the anisotropic (deformation) of the condensates, and the critical rotation frequency for vortex excitation are provided analytically. Owing to the action of spin-orbit coupling, the effective mass of the condensates is spatially dependent and asymmetric in two phases, resulting in distinct quadrupole modes, deformations, and vortex excitations in the two phases, especially when the LHY correction is present. The LHY correction promotes the system in the zero-momentum phase with unpolarized vortex states, while the spin-orbit coupling promotes the emergence of a plane wave phase with polarized vortex states. The phase transition and vortex excitation can be well manipulated by spin-orbit coupling, Raman coupling, LHY correction, and external potential.

Ziyu Chen, Jiaxin Wang, Qi Jie +1 more

Wolfgang Ketterle