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Fermi hole level

Here the coefficients Cn and Cv are of no interest the meanings of the remaining symbols are clear from Fig. 4, where FF is the Fermi level at a thermodynamic equilibrium (in the dark) FnF and FPFP are Fermi quasi levels (in the presence of illumination) for electrons and holes, respectively Fs in Fig. 4 denotes the bending of the bands near the surface ( Fb is taken to be greater than zero if the bands are bent upward). [Pg.167]

Suppose (5) that the Fermi quasi levels for electrons and holes remain constant throughout the bulk of the crystal (for all x), as shown in Fig. 4 (the straight lines FnFn and FPFP are horizontal). This occurs with a crystal of fairly small size and with a sufficiently low coefficient of light... [Pg.167]

Fig. 10-28. Polarization curves for cell reactions of photoelectrolytic decomposition of water at a photoezcited n-type anode and at a metal cathode solid curve M = cathodic polarization curve of hydrogen evolution at metal cathode solid curve n-SC = anodic polarization curve of oxygen evolution at photoezcited n-type anode (Fermi level versus current curve) dashed curve p-SC = quasi-Fermi level of interfadal holes as a ftmction of anodic reaction current at photoezcited n-type anode (anodic polarization curve r re-sented by interfacial hole level) = electrode potential of two operating electrodes in a photoelectrolytic cell p. sc = inverse overvoltage of generation and transport ofphotoezcited holes in an n-type anode. Fig. 10-28. Polarization curves for cell reactions of photoelectrolytic decomposition of water at a photoezcited n-type anode and at a metal cathode solid curve M = cathodic polarization curve of hydrogen evolution at metal cathode solid curve n-SC = anodic polarization curve of oxygen evolution at photoezcited n-type anode (Fermi level versus current curve) dashed curve p-SC = quasi-Fermi level of interfadal holes as a ftmction of anodic reaction current at photoezcited n-type anode (anodic polarization curve r re-sented by interfacial hole level) = electrode potential of two operating electrodes in a photoelectrolytic cell p. sc = inverse overvoltage of generation and transport ofphotoezcited holes in an n-type anode.
As shown in Fig. 3.6, for intrinsic (undoped) semiconductors the number of holes equals the number of electrons and the Fermi energy level > lies in the middle of the band gap. Impurity doped semiconductors in which the majority charge carriers are electrons and holes, respectively, are referred to as n-type and p-type semiconductors. For n-type semiconductors the Fermi level lies just below the conduction band, whereas for p-type semiconductors it lies just above the valence band. In an intrinsic semiconductor tbe equilibrium electron and bole concentrations, no and po respectively, in tbe conduction and valence bands are given by ... [Pg.128]

Similarly, one can derive an equation for a p-type semiconductor, where the distance between the Fermi energy level and the valence band is a logarithmic function of acceptor impurity concentration. As the acceptor impurity increases so too does the hole concentration in valence band, with the Fermi level moving closer to the valence band. [Pg.129]

Fig. 7.1 Position of band edges and photodecomposition Fermi energies levels of various non-oxide semiconductors. E(e,d) represents decomposition energy level by electrons, while E(h,d) represents the decomposition energy level for holes vs normal hydrogen electrode (NHE). E(VB) denotes the valence band edge, E(CB) denotes the conduction band edge. E(H2/H20) denotes the reduction potential of water, and (H2O/O2) the oxidation potential of water, both with reference to NHE. Fig. 7.1 Position of band edges and photodecomposition Fermi energies levels of various non-oxide semiconductors. E(e,d) represents decomposition energy level by electrons, while E(h,d) represents the decomposition energy level for holes vs normal hydrogen electrode (NHE). E(VB) denotes the valence band edge, E(CB) denotes the conduction band edge. E(H2/H20) denotes the reduction potential of water, and (H2O/O2) the oxidation potential of water, both with reference to NHE.
Degenerate doping The amount of doping required to bring the Fermi energy level to a level comparable to the conduction band energy for electrons and the valence band energy for holes. [Pg.180]

Fig. 4.14 (a) Two-photon induced photoluminescence from a single gold nanorod. (b) Symmetry points and axes in the first Brilloiun zone of gold, (c) Band structures of gold near the X and L symmetric points. The notations sp and d denote, respectively, the sp conduction band and the d valence band. The dashed line Fermi energy level. h(Opi photon energy of photoluminescence radiated through recombination of an electron-hole pair... [Pg.150]

Intrinsic semiconductors are undoped and the concentration of conduction band electrons equals that of valence band holes, i.e. n = p. In this case, the Fermi energy level is located near the centre of the bandgap. [Pg.327]

The electrons in their spatial distribution in pairs are considered between the limit of non-interaction (A=0) and the limit of interaction (A=l) they carry, at any level of parameterized interaction 2, by their double goer (doppelganger), modeling the virtual ability to inverse its spin, thus defining the so-called Fermi hole, see the Volume II of the present five-volume work (Putz, 2016c)... [Pg.211]

This way, the Fermi hole is the quantum measure of the Pauli Exclusion principle, at the level of exchange energy (because it takes into account the reciprocal orientation of spin) and correlation (because it generalizes the Coulombian classical interaction). [Pg.211]

X-ray photoelectron spectroscopy yttria-stabilized zirconia kinetic term related to electrons kinetic term related to electron holes diffusion coeffrcierrt elementary charge concentration of electrons energy level of the conduction band energy level of species i Fermi energy level band gap... [Pg.129]

When the Fermi energy level, Ep, is only shghtly populated (E - Ep) kT then the number of electrons and electron holes, respectively in the conduction and the valence band, may be expressed by Equations (4.9) and (4.10). Then Equations (4.7) and (4.8) assmne the following forms ... [Pg.141]

The ELI variant (ELI-D) based on the correlation between same-spin electrons (described by the Fermi hole) is a robust bonding descriptor directly connected with the Pauli principle. Thus, it can be used already at the independent particle level of theory. ELl-D displays high values in spatial regions that can be connected with the conception of atomic shells, lone pairs, and bonds. In analogy to... [Pg.166]

The distributions of excess, or injected, carriers are indicated in band diagrams by so-called quasi-Fermi levels for electrons, Ep or holes, These... [Pg.127]

Electrons excited into the conduction band tend to stay in the conduction band, returning only slowly to the valence band. The corresponding missing electrons in the valence band are called holes. Holes tend to remain in the valence band. The conduction band electrons can estabUsh an equihbrium at a defined chemical potential, and electrons in the valence band can have an equiUbrium at a second, different chemical potential. Chemical potential can be regarded as a sort of available voltage from that subsystem. Instead of having one single chemical potential, ie, a Fermi level, for all the electrons in the material, the possibiUty exists for two separate quasi-Fermi levels in the same crystal. [Pg.116]


See other pages where Fermi hole level is mentioned: [Pg.145]    [Pg.127]    [Pg.309]    [Pg.196]    [Pg.273]    [Pg.534]    [Pg.7]    [Pg.82]    [Pg.84]    [Pg.94]    [Pg.121]    [Pg.135]    [Pg.309]    [Pg.72]    [Pg.213]    [Pg.149]    [Pg.3851]    [Pg.260]    [Pg.250]    [Pg.251]    [Pg.351]    [Pg.128]    [Pg.345]    [Pg.116]    [Pg.84]    [Pg.48]    [Pg.120]    [Pg.332]    [Pg.332]    [Pg.392]    [Pg.225]   
See also in sourсe #XX -- [ Pg.262 ]




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