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arXiv · 1412.7895

Quantum trajectories under frequent measurements in non-Markovian environment

Luting Xu·Xin-Qi Li
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Abstract

In this work we generalize the quantum trajectory (QT) theory from Markovian to non-Markovian environments. We model the non-Markovian environment by using a Lorentzian spectral density function with bandwidth ($\Lambda$), and find perfect "scaling" property with the measurement frequency ($\tau^{-1}$) in terms of the scaling variable $x=\Lambda\tau$. Our result bridges the gap between the existing QT theory and the Zeno effect, by rendering them as two extremes corresponding to $x\to\infty$ and $x\to 0$, respectively. This $x$-dependent criterion improves the idea of using $\tau$ alone, and quantitatively identifies the validity condition of the conventional QT theory.

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Luting Xu, Xin-Qi Li. 2014-12-26. Quantum trajectories under frequent measurements in non-Markovian environment. https://doi.org/10.1103/physreva.94.032130

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