Noise-free measurement of harmonic oscillators with instantaneous interactions.
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 or circuit QED, and even intracavity optical fields.
França Santos
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Departamento de Física, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil. msantos@fisica.ufmg.br
Giedke
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Solano
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