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

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.

16 pages, 2 figures, the final version is available on the OSA website

References in corpus (4)

• A Straightforward Introduction to Continuous Quantum Measurement
• Quantum Kalman Filtering and the Heisenberg Limit in Atomic Magnetometry
• Filtering equation for a measurement of a coherent channel
• Squeezed coherent state undergoing a continuous nondemolition observation

Cited by in corpus (1)

• Quantum trajectories for environment in superposition of coherent states