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Possible realization of Josephson charge qubits in two coupled Bose-Einstein condensates

Zeng-Bing Chen·Yong-De Zhang
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Abstract

We demonstrate that two coupled Bose-Einstein condensates (BEC) at zero temperature can be used to realize a qubit which is the counterpart of Josephson charge qubits. The two BEC are weakly coupled and confined in an asymmetric double-well trap. When the "charging energy" of the system is much larger than the Josephson energy and the system is biased near a degeneracy point, the two BEC represent a qubit with two states differing only by one atom. The realization of the BEC qubits in realistic BEC experiments is briefly discussed.

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Zeng-Bing Chen, Yong-De Zhang. 2002-01-16. Possible realization of Josephson charge qubits in two coupled Bose-Einstein condensates. https://doi.org/10.1103/physreva.65.022318

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