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arXiv · 0807.3475

Coherent-incoherent transition in a Cooper-pair-box coupled to a quantum oscillator: an equilibrium approach

Ying-Hua Huang·Hang Wong·Zhi-De Chen
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Abstract

Temperature effect on quantum tunneling in a Cooper-pair-box coupled to a quantum oscillator is studied by both numerical and analytical calculations. It is found that, in strong coupling regions, coherent tunneling of a Cooper-pair-box can be destroyed by its coupling to a quantum oscillator and the tunneling becomes thermally activated as the temperature rises, leading to failure of the Cooper-pair-box. The transition temperature between the coherent tunneling and thermo-activated hopping is determined and physics analysis based on small polaron theory is also provided.

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Ying-Hua Huang, Hang Wong, Zhi-De Chen. 2008-07-22. Coherent-incoherent transition in a Cooper-pair-box coupled to a quantum oscillator: an equilibrium approach. https://doi.org/10.2174/1874186x00801010019

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