Directional correlations in quantum walks with two particles

Abstract

Quantum walks on a line with a single particle possess a classical analogue.Involving more walkers opens up the possibility of studying collective quantum effects, such as many-particle correlations.In this context, entangled initial states and the indistinguishability of the particles play a role.We consider the directional correlations between two particles performing a quantum walk on a line.For non-interacting particles, we find analytic asymptotic expressions and give the limits of directional correlations.We show that by introducing δ-interaction between the particles, one can exceed the limits for non-interacting particles.© IOP Publishing Ltd and Deutsche Physikalische Gesellschaft.