Physics of the Solid State

Relaxation dynamics of superconducting Josephson cubits in a strong alternating field

A. I. Gel’man, Сатанин Аркадий Михайлович

Published Nov 1, 2010• 0 citations

Abstract

The quantum trajectory method has been applied to study the influence of noise on the level populations of a cubit in separate realizations of the experiment and to follow the transition to the averaged dynamics obtained by multiple measurements of the cubit state. As an example of applying the developed method, the influence of noise on the interference pattern appearing in amplitude spectroscopy due to the Landau-Zener transitions in an alternating field has been analyzed. The influence of the number of repeated measurements and fluctuations in the phase of the exciting pulse during formation of the response of a cubit to the external field has been studied, which made it possible to interpret recent experiments from the viewpoint of single realizations and averaged dynamics.

DOI: 10.1134/s106378341011003x

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