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Quantum trajectories for Brownian motion

Walter T. Strunz·Lajos Diosi·Nicolas Gisin·Ting Yu
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Abstract

We present the stochastic Schroedinger equation for the dynamics of a quantum particle coupled to a high temperature environment and apply it the dynamics of a driven, damped, nonlinear quantum oscillator. Apart from an initial slip on the environmental memory time scale, in the mean, our result recovers the solution of the known non-Lindblad quantum Brownian motion master equation. A remarkable feature of our approach is its localization property: individual quantum trajectories remain localized wave packets for all times, even for the classically chaotic system considered here, the localization being stronger the smaller $\hbar$.

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Walter T. Strunz, Lajos Diosi, Nicolas Gisin, Ting Yu. 1999-07-30. Quantum trajectories for Brownian motion. https://doi.org/10.1103/physrevlett.83.4909

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