Existence and computation of generalized Wannier functions for non-periodic systems in two dimensions and higher

@article{Stubbs2022ExistenceAC,
  title={Existence and computation of generalized Wannier functions for non-periodic systems in two dimensions and higher},
  author={Kevin D. Stubbs and Alexander B. Watson and Jianfeng Lu},
  journal={ArXiv},
  year={2022},
  volume={abs/2003.06676}
}
Exponentially-localized Wannier functions (ELWFs) are a basis of the Fermi projection of a material consisting of functions which decay exponentially fast away from their maxima. When the material is insulating and crystalline, conditions which guarantee existence of ELWFs in dimensions one, two, and three are well-known, and methods for constructing the ELWFs numerically are well-developed. We consider the case where the material is insulating but not necessarily crystalline, where much less… 
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