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arXiv · 1104.4050

Crossover between ballistic and diffusive transport: The Quantum Exclusion Process

Viktor Eisler
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Abstract

We study the evolution of a system of free fermions in one dimension under the simultaneous effects of coherent tunneling and stochastic Markovian noise. We identify a class of noise terms where a hierarchy of decoupled equations for the correlation functions emerges. In the special case of incoherent, nearest-neighbour hopping the equation for the two-point functions is solved explicitly. The Green's function for the particle density is obtained analytically and a timescale is identified where a crossover from ballistic to diffusive behaviour takes place. The result can be interpreted as a competition between the two types of conduction channels where diffusion dominates on large timescales.

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Viktor Eisler. 2011-04-20. Crossover between ballistic and diffusive transport: The Quantum Exclusion Process. https://doi.org/10.1088/1742-5468%2F2011%2F06%2Fp06007

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