It is often stated in paper abstracts that

“One cannot build [[Wannier Functions]] for [[Topological Insulators]]”,

“One cannot build exponentially localized [[Wannier Functions]] for [[Topological Insulators]]”,

and when one reads the introduction, the statement changes to

Where does this distinction come from, and is it relevant for building WFs in practice?

The insulator picture

In a seminal paper [1], Prodan builds on top of Kohn’s idea of [[Nearsightedness]] in electronic matter.

SSH model

References

[1]
E. Prodan, “Nearsightedness of electronic matter in one dimension,” Physical Review B, vol. 73, no. 8, p. 085108, Feb. 2006, doi: 10.1103/PhysRevB.73.085108.