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Strong coupling of a qubit to shot noise

Udo Hartmann·Frank K. Wilhelm
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Abstract

We perform a nonperturbative analysis of a charge qubit in a double quantum dot structure coupled to its detector. We show that strong detector-dot interaction tends to slow down and halt coherent oscillations. The transitions to a classical and a low-temperature quantum overdamping (Zeno) regime are studied. In the latter, the physics of the dissipative phase transition competes with the effective shot noise.

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Udo Hartmann, Frank K. Wilhelm. 2005-08-04. Strong coupling of a qubit to shot noise. https://doi.org/10.1103/physrevb.75.165308

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