Fermi Surface Nesting¶

Fermi surface nesting means that there are two parallel pieces of a Fermi surface, such that a single q-vector can connect many points. A one dimensional metal automatically has perfect nesting because the Fermi surface consists of two points at \(k= \pm k_F\).

For higher dimensions, the Fermi surface is circular or spherical for free-electron like single-band medal and hence nesting will not be perfect but systems with strong interaction (or quasi 1D bands) can have Fermi surface nesting.

Not all CDW are driven by nesting, and not all Fermi surface topologies with a good nesting condition result in CDW instability Gruner et al, Density Waves in Solids, Perseus Publishing (2000)