Correlation effects in a discrete quantum random walk
نویسندگان
چکیده
We introduce memory-dependent discrete-time quantum random walk models by adding uncorrelated memory terms and also by modifying the Hamiltonian of the walker to include couplings with memory-keeping agents. We next study numerically the correlation effects in these models. We also propose a correlation exponent as a relevant and promising tool for investigation of correlation or memory (hence non-Markovian) effects. Our analysis can easily be applied to more realistic models in which different regimes may emerge because of competition between different underlying physical mechanisms. PACS numbers: 03.67.−a, 05.40.Fb, 03.65.Yz (Some figures in this article are in colour only in the electronic version)
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