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arXiv · 1410.5962

Relaxation, decoherence and steady-state population inversion in qubits doubly dressed by microwave and radiofrequency fields

A. P. Saiko·R. Fedaruk·S. A. Markevich
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Abstract

The coherent dynamics of relaxing spin qubits driven by a classical bichromatic field comprising a strong resonant component and a weaker component with a frequency close to the strong-field Rabi frequency is studied. The double dressing by the bichromatic field modifies dephasing and dissipation processes. We demonstrate that detuning of the weaker-field frequency from the strong-field Rabi frequency prolongs the decay of Rabi oscillations between some doubly dressed states. The sensitivity of Rabi oscillations to the modified detuning-dependent relaxation is illustrated for nitrogen-vacancy qubits in diamond. We discuss a steady-state population inversion of the doubly dressed-state levels.

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A. P. Saiko, R. Fedaruk, S. A. Markevich. 2014-10-22. Relaxation, decoherence and steady-state population inversion in qubits doubly dressed by microwave and radiofrequency fields. https://doi.org/10.1088/0953-4075%2F47%2F15%2F155502

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