Quantum continual measurements and a posteriori collapse on CCR |
| |
Authors: | V P Belavkin |
| |
Institution: | (1) Department of Mathematics, University of Nottingham, University Park, NG7 2RD Nottingham, England;(2) Present address: M.I.E.M., B. Vusovski Street 3/12, 109028 Moscow, Russia |
| |
Abstract: | A quantum stochastic model for the Markovian dynamics of an open system under the nondemolition unsharp observation which is continuous in time, is given. A stochastic equation for the posterior evolution of a quantum continuously observed system is derived and the spontaneous collapse (stochastically continuous reduction of the wave packet) is described. The quantum Langevin evolution equation is solved for the case of a quasi-free Hamiltonian in the initial CCR algebra with a linear output channel, and the posterior dynamics corresponding to an initial Gaussian state is found. It is shown for an example of the posterior dynamics of a quantum oscillator that any mixed state under a complete nondemolition measurement collapses exponentially to a pure Gaussian one. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|