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Measuring irreversible dynamics of a quantum harmonic oscillator

Giovanna Morigi·Enrique Solano·Berthold-Georg Englert·Herbert Walther
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Abstract

We show that the unitary evolution of a harmonic oscillator coupled to a two-level system can be undone by a suitable manipulation of the two-level system -- more specifically: by a quasi-instantaneous phase change. This enables us to isolate the dissipative evolution to which the oscillator may be exposed in addition. With this method we study the decoherence of a photon mode in cavity QED, and that of the quantized harmonic motion of trapped ions. We comment on the relation to spin echoes and multi-path interferometry.

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Giovanna Morigi, Enrique Solano, Berthold-Georg Englert, Herbert Walther. 2001-08-17. Measuring irreversible dynamics of a quantum harmonic oscillator. https://doi.org/10.1103/physreva.65.040102

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