Nondemolition observation of a free quantum particle.
نویسندگان
چکیده
A stochastic model of a continuous nondemolition observation of a free quantum Brownian motion is presented. The nonlinear stochastic wave equation describing the posterior dynamics of the observed quantum system is solved in a Gaussian case for a free particle of mass m > 0. It is shown that the dispersion of the wave packet does not increase to infinity like for the free unobserved particle but tends to the finite limit τ 2∞ = (~/2λm) 1/2 where λ is the accuracy coefficient of an indirect nondemolition measurement of the particle position, and ~ is Planck constant.
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عنوان ژورنال:
- Physical review. A, Atomic, molecular, and optical physics
دوره 45 3 شماره
صفحات -
تاریخ انتشار 1992