no code implementations • 7 Jan 2021 • Jianfeng Lu, Kevin D. Stubbs
In two and three spatial dimensions, it is well understood for periodic insulators that exponentially-localized Wannier functions exist if and only if there exists an orthonormal basis for the Fermi projection with finite second moment (i. e. all basis elements satisfy $\int |\boldsymbol{x}|^2 |w(\boldsymbol{x})|^2 \,\text{d}{\boldsymbol{x}} < \infty$).
Mathematical Physics Mesoscale and Nanoscale Physics Mathematical Physics
