Coulomb gap: How a metal film becomes an insulator
Electron tunneling measurements of the density of states (DOS) in ultrathin Be films reveal that a correlation gap mediates their insulating behavior. In films with sheet resistance R<5000Ω the correlation singularity appears as the usual perturbative ln(V) Efros-Shklovskii Coulomb gap spectrum finally emerges in the highest R films. Transport measurements of films which display this gap are well described by a universal variable range hopping law R(T) = (h/2e2)exp(T0/T)1/2. © 2000 The American Physical Society.
Publication Source (Journal or Book title)
Physical Review Letters
Butko, V., DiTusa, J., & Adams, P. (2000). Coulomb gap: How a metal film becomes an insulator. Physical Review Letters, 84 (7), 1543-1546. https://doi.org/10.1103/PhysRevLett.84.1543