Fermi energy

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Related to Fermi momentum: Fermi energy, Fermi temperature

Fermi energy

or

Fermi level

n
(General Physics) the level in the distribution of electron energies in a solid at which a quantum state is equally likely to be occupied or empty
[C20: named after Enrico Fermi]
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014
References in periodicals archive ?
where V(p, p') is the corresponding interaction amplitude; [p.sub.F] and [m.sup.*] = [p.sub.F]/[v.sub.F] are the Fermi momentum and the neutron effective mass, respectively, so that [p.sub.F][m.sup.*]/[[pi].sup.2] is the density of states near the Fermi surface.
They are the Fermi momentum m[[upsilon].sub.F] and the Compton momentum mc.
with [k.sub.F] being the Fermi momentum and 0 < [beta] < [alpha] < 1.
The momentum of nucleons (in each nucleus) is chosen between zero and local Fermi momentum [= [square root of (2[m.sub.i][V.sub.i]([??]))]; [V.sub.i]([??]) is the potential energy of nucleon i].
Furthermore, high-energy electron scattering shows that internucleon short-range repulsive force forms correlated high-momentum neutron-proton pairs and thus, in exotic nuclei, protons are more probable to have a momentum greater than the Fermi momentum in comparison to neutrons [51].
They are: the Fermi momentum m[v.sub.F] and the Compton momentum mc.
This conventional choice for the single-particle spectrum, however, is not very appealing as it leads to a gap at the Fermi surface; the propagator for single-particle states with momenta below the Fermi momentum [k.sub.F] is described in terms of a bound single-particle energy while the corresponding spectrum for the particle states starts at the kinetic energy for the momentum [k.sub.F].
In this respect, we use of (46) and (47) with introducing of the Fermi momentum [MATHEMATICAL EXPRESSION NOT REPRODUCIBLE IN ASCII], for instance, for such material as Al with [c.sub.l] = 6.26 * [10.sup.3] m/sec and [c.sub.t] = 3.08 * [10.sup.3] m/sec at room temperature [9], and [p.sub.f] = 1.27 * [10.sup.-24] kg*m/sec we may estimate [m.sub.l] = [p.sub.f]/[c.sub.l] = 2 * [10-.sup.28] kg and [m.sub.t] = [p.sub.f]/[c.sub.t] = 4 * [10.sup.-28] kg.