Ground states and dynamics of rotating Bose-Einstein condensates

Abstract

Since its realization in dilute bosonic atomic gases [7], [23], Bose-Einstein condensation of alkali atoms and hydrogen has been produced and studied extensively in the laboratory [1], and has permitted an intriguing glimpse into the macroscopic quantum world. In view of potential applications [38], [61], [63], the study of quantized vortices, which are well-known signatures of superfluidity, is one of the key issues. In fact, bulk superfluids are distinguished from normal fluids by their ability to support dissipationless flow. Such persistent currents are intimately related to the existence of quantized vortices, which are localized phase singularities with integer topological charge [39]. The superfluid vortex is an example of a topological defect that is well known in superconductors [52] and in liquid helium [33]. The occurrence of quantized vortices in superfluids has been the focus of fundamental theoretical and experimental work [33]. Different research groups have obtained quantized vortices in Bose-Einstein condensates (BECs) experimentally, e.g., the JILA group [35], [57], the ENS group [56] and the MIT group [1], [32]. Currently, there are at least two typical ways to generate quantized vortices from a BEC ground state: (i) impose a laser beam rotating with an angular velocity on the magnetic trap holding the atoms to create a harmonic anisotropic potential [51], [4], [75]; or (ii) add to the stationary magnetic trap a narrow, moving Gaussian potential, representing a far-blue detuned laser [49], [50], [24], [25], [10], [12].