Topological delocalization in the completely disordered two-dimensional quantum walk

  title={Topological delocalization in the completely disordered two-dimensional quantum walk},
  author={J'anos K. Asb'oth and Arindam Mallick},
  journal={arXiv: Quantum Physics},
We investigate numerically and theoretically the effect of spatial disorder on two-dimensional split-step discrete-time quantum walks with two internal "coin" states. Spatial disorder can lead to Anderson localization, inhibiting the spread of quantum walks, putting them at a disadvantage against their diffusively spreading classical counterparts. We find that spatial disorder of the most general type, i.e., position-dependent Haar random coin operators, does not lead to Anderson localization… 
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