Corrections to the Berry phase in a solid-state qubit due to low-frequency noise

PAULA I. VILLAR

San Carlos de Bariloche

Workshop; Driven Quantum Systems; 2016

ICTP

We present a quantum open-system approach to an-alyze the nonunitary dynamics of a superconductingqubit when it evolves under the influence of external noise. We consider the presence of longitudinal and transverse environmental fluctuations affecting the system's dynamics and model these fluctuations by defining their correlation function in time. By using a Gaussian-like noise correlation, we can study low- and high- frequency noise contribution to decoherence and implement our results in the computation of geometric phases in open quantum systems. We numerically study when the accumulated phase of a solid-state qubit can still be found close to the unitary (Berry) one. Our results can be used to explain experimental measurements of the Berry phase under high-frequency fluctuations and design experimental future setups when manipulating superconducting qubits.