Robustness of topologically protected edge states in quantum walk experiments with neutral atoms

  title={Robustness of topologically protected edge states in quantum walk experiments with neutral atoms},
  author={Thorsten Groh and Stefan Brakhane and Wolfgang Alt and Dieter Meschede and J'anos K. Asb'oth and Andrea Alberti},
  journal={Physical Review A},
Discrete-time quantum walks allow Floquet topological insulator materials to be explored using controllable systems such as ultracold atoms in optical lattices. By numerical simulations, we study the robustness of topologically protected edge states in the presence of decoherence in one- and two-dimensional discrete-time quantum walks. We also develop a simple analytical model quantifying the robustness of these edge states against either spin or spatial dephasing, predicting an exponential… 

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