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arXiv · 0706.4029

Dynamics of a qubit coupled to a broadened harmonic mode at finite detuning

F. Nesi·M. Grifoni·E. Paladino
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Abstract

We study the dynamics of a symmetric two-level system strongly coupled to a broadened harmonic mode. Upon mapping the problem onto a spin-boson model with peaked spectral density, we show how analytic solutions can be obtained, at arbitrary detuning and finite temperatures, in the case of large Q-factors of the oscillator. In general {\em two} or more oscillation frequencies of the two-level particle are observed as a consequence of the entanglement with the oscillator. Our approximated analytical solution well agrees with numerical predictions obtained within the non-interacting blip approximation.

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F. Nesi, M. Grifoni, E. Paladino. 2007-06-27. Dynamics of a qubit coupled to a broadened harmonic mode at finite detuning. https://doi.org/10.1088/1367-2630%2F9%2F9%2F316

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