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Fractional Dynamical Behavior in Quantum Brownian Motion

Kyungsik Kim·Y. S. Kong·M. K. Yum·J. T. Kim
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Abstract

The dynamical behavior for a quantum Brownian particle is investigated under a random potential of the fractional iterative map on a one-dimensional lattice. For our case, the quantum expectation values can be obtained numerically from the wave function of the fractional Schr$\ddot{o}$dinger equation. Particularly, the square of mean displacement which is ensemble-averaged over our configuration is found to be proportional approximately to $t^δ$ in the long time limit, where $δ$ $=$ $0.96 \pm 0.02$. The power-law behavior with scaling exponents $ε$ $=$ $0.98 \pm 0.02$ and $θ$ $=$ $ 0.51 \pm 0.01$ is estimated for $ \bar {{< p(t) >}^2}$ and $ \bar {{< f(t) >}^2}$, and the result presented is compared with other numerical calculations.

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Kyungsik Kim, Y. S. Kong, M. K. Yum, J. T. Kim. 2002-03-29. Fractional Dynamical Behavior in Quantum Brownian Motion. https://arxiv.org/abs/cond-mat/0203602

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