nearFermilevel
nearFermilevel is a term used in condensed matter physics to describe a region of electronic states that lie close to the Fermi energy in a solid. It is used informally to indicate the subset of states that predominantly influence low-temperature properties, such as transport and superconductivity.
There is no formal universal definition for nearFermilevel; typically, “near” means within a small energy window
Occupation probabilities change rapidly near EF due to the Fermi-Dirac distribution, making near-EF states especially relevant
The nearFermilevel region is probed by spectroscopic techniques such as angle-resolved photoemission spectroscopy (ARPES) and scanning
Examples and contexts include graphene, where the linear dispersion leads to a vanishing DOS at the Dirac
Limitations include the fact that EF itself can shift with doping, pressure, or temperature; therefore, the
See also: Fermi level, Density of states, Fermi-Dirac distribution, ARPES, STM.