arXiv:1212.3512 · Journal of the Optical Society of America B

Posterior quantum dynamics for a continuous diffusion observation of a coherent channel

Anita Magdalena Dąbrowska, P. Staszewski

Published Oct 17, 2012• 1 citation

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.

DOI: 10.1364/josab.29.003072

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