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arXiv · 2404.09106

Quantum transport in randomized quantum graphs

Alison A. Silva·D. Bazeia·Fabiano M. Andrade
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Abstract

This work deals with quantum transport in open quantum graphs. We consider the case of complete graphs on $n$ vertices with an edge removed and attached to two leads, to represent the entrance and exit channels, from where we calculate the transmission coefficient. We include the possibility of several vertices being connected or not and associate it with a randomization parameter $p$. To implement the calculation, we had to introduce the transmission coefficient of randomized quantum graphs (RQG), and we also proposed a procedure to obtain the exact and approximate but reliable results for such transmission coefficients. The main results show that the transport is importantly affected by the removal of connections between pairs of vertices, but they also indicate the presence of a region where the transmission is fully suppressed, even when the number of edge removal is not too small.

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Alison A. Silva, D. Bazeia, Fabiano M. Andrade. 2024-12-20. Quantum transport in randomized quantum graphs. https://doi.org/10.1063/5.0239742

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