Compactly supported Wannier functions and strictly local projectors

  title={Compactly supported Wannier functions and strictly local projectors},
  author={Pratik Sathe and Fenner Harper and Rahul Roy},
  journal={Journal of Physics A: Mathematical and Theoretical},
Wannier functions that are maximally localized help in understanding many properties of crystalline materials. In the absence of topological obstructions, they are at least exponentially localized. In some cases such as flat-band Hamiltonians, it is possible to construct Wannier functions that are even more localized, so that they are compactly supported thus having zero support outside their corresponding locations. Under what general conditions is it possible to construct compactly supported… 
3 Citations
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