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Incoming links: Electrons in Glass by Nevill Francis Mott
Nevill Mott Created 2026-10-24 Updated 2026-11-05
Nevill Mott investigated electronic conduction in disordered solids, including glasses and amorphous semiconductors. When states are localized, a carrier can move by thermally assisted hopping rather than ordinary propagation through an extended band. The useful hopping distance balances weak overlap at long range against the availability of energetically accessible states. This connects a temperature-dependent conductivity with both the spatial localization and energy distribution of electronic states.[ref]
Electrons in Glass by Nevill Francis Mott. Nobel lecture, localized states, mobility and hopping conduction
Portrait of Nevill Mott
. GFHund / Friedrich Hund estate; existing portrait crop. Creative Commons Attribution 3.0 Unported selected from the File's alternatives; separate GFDL option not used., via Wikimedia Commons. Source.
Semiconductor transport evidence for localization Created 2026-10-18 Updated 2026-10-20
Nevill Francis Mott's 1977 lecture discusses silicon deposited in a glow discharge. Injected electrons provided a drift-mobility readout; electrical conductivity and temperature dependence tested localized-state transport and excitation toward a mobility edge. Varying temperature distinguishes transport regimes. The lecture gives no contact geometry or timing circuit here, so none is inferred. Its Figure 2 is schematic, not measured data.[ref]
Electrons in Glass by Nevill Francis Mott. Electrons in Glass, pp.404–406, Fig.2 and discussion of glow-discharge-deposited silicon; inspected institutional mirror www.nevis.columbia.edu/~haas/documents/physics_nobel_lectures/physics71-80-2.pdf
This evidence motivates a transport question beyond the closed-chain eigenvalue problem: how does a prepared charge disturbance move under the conditions of a real sample? The numerical figures above supply neither drift-mobility measurements nor a model of the deposition process. Finite-size concentration alone cannot reproduce an experimental electrical conductivity curve.
Finite temperature permits phonon-assisted hopping between localized eigenstates or thermal excitation toward a mobility edge; localized states therefore need not imply zero measured electrical conductivity at every nonzero temperature.[ref]
Electrons in Glass by Nevill Francis Mott. Electrons in Glass, pp.405,407, localized-state hopping and thermal excitation
Real dephasing destroys the relative wave phases needed for long-path interference. Observing coherent confinement requires the distance over which those wave phases survive to be long enough to explore the localized region, and the sample to be large enough to resolve it. Temperature alone is not an automatic switch: the actual inelastic processes set the relevant scales. Static elastic wave scattering preserves coherence within each realization. Loss of the ensemble-averaged coherent field through random wave phases is therefore not, by itself, physical dephasing of an individual sample.