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Conditional evolution in single-atom cavity QED

Andrei N. Soklakov·Ruediger Schack
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Abstract

We consider a typical setup of cavity QED consisting of a two-level atom interacting strongly with a single resonant electromagnetic field mode inside a cavity. The cavity is resonantly driven and the output undergoes continuous homodyne measurements. We derive an explicit expression for the state of the system conditional on a discrete photocount record. This expression takes a particularly simple form if the system is initially in the steady state. As a byproduct, we derive a general formula for the steady state that had been conjectured before in the strong driving limit.

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Andrei N. Soklakov, Ruediger Schack. 2001-06-15. Conditional evolution in single-atom cavity QED. https://doi.org/10.1103/physreva.65.013804

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