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Testing Broken U(1) Symmetry in a Two-Component Atomic Bose-Einstein Condensate

C. P. Search·P. R. Berman
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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.

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C. P. Search, P. R. Berman. 2000-12-25. Testing Broken U(1) Symmetry in a Two-Component Atomic Bose-Einstein Condensate. https://doi.org/10.1103/physreva.64.013612

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