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Continuous measurement with traveling wave probes

Andrew Silberfarb·Ivan H. Deutsch
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Abstract

We consider the use of a traveling wave probe to continuously measure the quantum state of an atom in free space. Unlike the more familiar cavity QED geometry, the traveling wave is intrinsically a multimode problem. Using an appropriate modal decomposition we determine the effective measurement strength for different atom-field interactions and different initial states of the field. These include the interaction of a coherent-state pulse with an atom, the interaction of a Fock-state pulse with an atom, and the use of Faraday rotation of a polarized laser probe to perform a QND measurement on an atomic spin.

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Andrew Silberfarb, Ivan H. Deutsch. 2003-08-01. Continuous measurement with traveling wave probes. https://doi.org/10.1103/physreva.68.013817

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