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arXiv · 0805.0645

Geometric phase of a two-level system in a dissipative environment

Kazuo Fujikawa·Ming-Guang Hu
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Abstract

The geometric (Berry) phase of a two-level system in a dissipative environment is analyzed by using the second-quantized formulation, which provides a unified and gauge-invariant treatment of adiabatic and nonadiabatic phases and is thus applicable to a quantitative analysis of transitional regions away from ideal adiabaticity. In view of the recent experimental observation of the Berry phase in a superconducting qubit, we illustrate our formulation for a concrete adiabatic case in the Ohmic dissipation. The correction to the total phase together with the geometry-dependent dephasing time is given in a transparent way. The behavior of the geometric phase away from ideal adiabaticity is also analyzed in some detail.

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Kazuo Fujikawa, Ming-Guang Hu. 2009-05-09. Geometric phase of a two-level system in a dissipative environment. https://doi.org/10.1103/physreva.79.052107

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