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arXiv · 1811.09520

Eigenvalue Measurement of Topologically Protected Edge states in Split-Step Quantum Walks

Thomas Nitsche·Tobias Geib·Christoph Stahl·Lennart Lorz·Christopher Cedzich·Sonja Barkhofen·Reinhard F. Werner·Christine Silberhorn
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Abstract

We study topological phenomena of quantum walks by implementing a novel protocol that extends the range of accessible properties to the eigenvalues of the walk operator. To this end, we experimentally realise for the first time a split-step quantum walk with decoupling, which allows for investigating the effect of a bulk-boundary while realising only a single bulk configuration. We approximate the symmetry protected edge states with high similarities and read out the phase relative to a reference for all modes. In this way we observe eigenvalues which are distinguished by the presence or absence of sign flips between steps. Furthermore, the results show that investigating a bulk-boundary with a single bulk is experimentally feasible when decoupling the walk beforehand.

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Thomas Nitsche, Tobias Geib, Christoph Stahl, Lennart Lorz, Christopher Cedzich, Sonja Barkhofen, Reinhard F. Werner, Christine Silberhorn. 2018-11-23. Eigenvalue Measurement of Topologically Protected Edge states in Split-Step Quantum Walks. https://doi.org/10.1088/1367-2630/ab12fa

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