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arXiv · 1105.4090

Quantum Decoherence of Single-Photon Counters

Virginia D'Auria·Noriyuki Lee·Taoufik Amri·Claude Fabre·Julien Laurat
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Abstract

The interaction of a quantum system with the environment leads to the so-called quantum decoherence. Beyond its fundamental significance, the understanding and the possible control of this dynamics in various scenarios is a key element for mastering quantum information processing. Here we report the quantitative probing of what can be called the quantum decoherence of detectors, a process reminiscent of the decoherence of quantum states in the presence of coupling with a reservoir. We demonstrate how the quantum features of two single-photon counters vanish under the influence of a noisy environment. We thereby experimentally witness the transition between the full-quantum operation of the measurement device to the "semi-classical regime", described by a positive Wigner function. The exact border between these two regimes is explicitely determined and measured experimentally.

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Virginia D'Auria, Noriyuki Lee, Taoufik Amri, Claude Fabre, Julien Laurat. 2011-09-02. Quantum Decoherence of Single-Photon Counters. https://doi.org/10.1103/physrevlett.107.050504

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