Testing Broken U(1) Symmetry in a Two-Component Atomic Bose-Einstein Condensate
arXiv:cond-mat/0012463 · doi:10.1103/PhysRevA.64.013612
Abstract
We present a scheme for determining if the quantum state of a small trapped Bose-Einstein condensate is a state with well defined number of atoms, a Fock state, or a state with a broken U(1) gauge symmetry, a coherent state. The proposal is based on the observation of Ramsey fringes. The population difference observed in a Ramsey fringe experiment will exhibit collapse and revivals due to the mean-field interactions. The collapse and revival times depend on the relative strength of the mean-field interactions for the two components and the initial quantum state of the condensate.
20 Pages RevTex, 3 Figures