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arXiv:2205.07732 · Physical Review A

Light-shift-induced behaviors observed in momentum-space quantum walks

Nikolai Bolik, Caspar Groiseau, Jerry H. Clark, Alexander Gresch, Siamak Dadras, Gil S. Summy, Yingmei Liu, Sandro Wimberger

Published Sep 7, 2022• 4 citations

Abstract

Over the last decade there have been many advances in studies of quantum walks (QWs) including a momentum-space QW recently realized in our spinor Bose-Einstein condensate system. This QW possessed behaviors that generally agreed with theoretical predictions; however, it also showed momentum distributions that were not adequately explained by the theory. We present a theoretical model which proves that the coherent dynamics of the spinor condensate is sufficient to explain the experimental data without invoking the presence of a thermal cloud of atoms as in the original theory. Our numerical findings are supported by an analytical prediction for the momentum distributions in the limit of zero-temperature condensates. This current model provides more complete explanations to the momentum-space QWs that can be applied to study quantum search algorithms and topological phases in Floquet-driven systems.

DOI: 10.1103/physreva.106.033307

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