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

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.

7 pages, 3 figures

References in corpus (6)

• Coupling Superconducting Qubits via a Cavity Bus
• Observation of Berry's Phase in a Solid State Qubit
• Geometric nature of the environment-induced Berry phase and geometric dephasing
• Geometric phase distributions for open quantum systems
• Geometric phases for mixed states and decoherence
• Adiabatic approximation in the second quantized formulation