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Groundstates of SU(2)-Symmetric Confined Bose Gas: Trap for a Schrödinger Cat

A. B. Kuklov·B. V. Svistunov
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Abstract

Conservation of the total isotopic spin S of a two-component Bose gas-like $^{87}$Rb-has a dramatic impact on the structure of the ground state. In the case when S is much smaller than the total number of particles N, the condensation of each of the two components occurs into two single-particle modes. The quantum wavefunction of such a groundstate is a Schrödinger Cat-a superposition of the phase separated classical condensates, the most "probable" state in the superposition corresponding to the classical groundstate in the sector of given N and S. After measurement of the spatial distribution of the densities of the two components, the Cat collapses into one of the classical condensate states.

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A. B. Kuklov, B. V. Svistunov. 2002-06-06. Groundstates of SU(2)-Symmetric Confined Bose Gas: Trap for a Schrödinger Cat. https://doi.org/10.1103/physrevlett.89.170403

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