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Noise-Free Measurement of Harmonic Oscillators with Instantaneous Interactions

M. Franca Santos·G. Giedke·E. Solano
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Abstract

We present a method of measuring the quantum state of a harmonic oscillator through instantaneous probe-system selective interactions of the Jaynes-Cummings type. We prove that this scheme is robust to general decoherence mechanisms, allowing the possibility of measuring fast-decaying systems in the weak-coupling regime. This method could be applied to different setups: motional states of trapped ions, microwave fields in cavity/circuit QED, and even intra-cavity optical fields.

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M. Franca Santos, G. Giedke, E. Solano. 2006-05-31. Noise-Free Measurement of Harmonic Oscillators with Instantaneous Interactions. https://doi.org/10.1103/physrevlett.98.020401

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