arXiv:2006.14883 · Physical review. E

Quantum walk on a graph of spins: Magnetism and entanglement

Kevissen Sellapillay, Alberto Verga

Published Mar 17, 2021• 7 citations

Abstract

We introduce a model of a quantum walk on a graph in which a particle jumps between neighboring nodes and interacts with independent spins sitting on the edges. Entanglement propagates with the walker. We apply this model to the case of a one-dimensional lattice to investigate its magnetic and entanglement properties. In the continuum limit, we recover a Landau-Lifshitz equation that describes the precession of spins. A rich dynamics is observed, with regimes of particle propagation and localization, together with spin oscillations and relaxation. Entanglement of the asymptotic states follows a volume law for most parameters (the coin rotation angle and the particle-spin coupling).

DOI: 10.1103/physreve.103.032123

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