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arXiv · 1811.04482

Hitting time for quantum walks of identical particles

Alexey A. Melnikov·Aleksandr P. Alodjants·Leonid E. Fedichkin
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Abstract

Quantum particles are known to be faster than classical when they propagate stochastically on certain graphs. A time needed for a particle to reach a target node on a distance, the hitting time, can be exponentially less for quantum walks than for classical random walks. It is however not known how fast would interacting quantum particles propagate on different graphs. Here we present our results on hitting times for quantum walks of identical particles on cycle graphs, and relate the results to our previous findings on the usefulness of identical interacting particles in quantum information theory. We observe that interacting fermions traverse cycle graphs faster than non-interacting fermions. We show that the rate of propagation is related to fermionic entanglement: interacting fermions keep traversing the cycle graph as long as their entanglement grows. Our results demonstrate the role of entanglement in quantum particles propagation. These results are of importance for understanding quantum transport properties of identical particles.

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Alexey A. Melnikov, Aleksandr P. Alodjants, Leonid E. Fedichkin. 2018-11-11. Hitting time for quantum walks of identical particles. https://doi.org/10.1117/12.2521982

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