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arXiv · 0904.2686

Noise-induced quantum coherence and persistent Rabi oscillations in a Josephson flux qubit

A. N. Omelyanchouk·S. Savel'ev·A. M. Zagoskin·E. Il'ichev·Franco Nori
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Abstract

We demonstrate theoretically the noise-stimulated enhancement of quantum coherence in a superconducting flux qubit. First, an external classical noise can increase the off-diagonal components of the qubit density matrix. Second, in the presence of noise, the Rabi oscillations survive for times significantly longer than the Rabi decay time in a noiseless system. These Rabi oscillations appear as a modulation of the forced response of the qubit to the ac driving field. These effects can be considered as a manifestation of quantum stochastic resonance and are relevant to experimental techniques, such as Rabi spectroscopy.

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A. N. Omelyanchouk, S. Savel'ev, A. M. Zagoskin, E. Il'ichev, Franco Nori. 2009-09-14. Noise-induced quantum coherence and persistent Rabi oscillations in a Josephson flux qubit. https://doi.org/10.1103/physrevb.80.212503

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