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arXiv · 1212.3512

A posterior quantum dynamics for a continuous diffusion observation of a coherent channel

Anita Dabrowska·Przemysław Staszewski
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Abstract

We present the Belavkin filtering equation for the intense balanced heterodyne detection in a unitary model of an indirect observation. The measuring apparatus modelled by a Bose field is initially prepared in a coherent state and the observed process is a diffusion one. We prove that this filtering equation is relaxing: any initial square-integrable function tends asymptotically to a coherent state with an amplitude depending on the coupling constant and the initial state of the apparatus. The time-development of a squeezed coherent state is studied and compared with the previous results obtained for the measuring apparatus prepared initially in the vacuum state.

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Anita Dabrowska, Przemysław Staszewski. 2012-12-14. A posterior quantum dynamics for a continuous diffusion observation of a coherent channel. https://doi.org/10.1364/josab.29.003072

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