Belavkin Filtering with Squeezed Light Sources

Anita Magdalena Dąbrowska, John Edward Gough

Published Aug 15, 2016• 8 citations

Abstract

We derive the filtering equation for Markovian systems undergoing ho-modyne measurement in the situation where the output processes being monitored are squeezed. The filtering theory applies to case where the system is driven by Fock noise (that, quantum input processes in a co-herent state) and where the output is mixed with a squeezed signal. It also applies to the case of a system driven by squeezed noise, but here there is a physical restriction to emission/absorption coupling only. For the special case of a cavity mode where the dynamics is linear, we are able to derive explicitly the filtered estimate pit(a) for the mode annihilator a based on the homodyne quadrature observations up to time t. In memory of Slava Belavkin. 1

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