Coulomb gap in a model with finite charge-transfer energy

Article

关键词: METAL-INSULATOR-TRANSITION;    DENSITY-OF-STATES;    DISORDERED-SYSTEMS;    CRITICAL-BEHAVIOR;    GLASS;    SEMICONDUCTOR;    CONDUCTIVITY;    SIMULATION;   

DOI  :  10.1103/PhysRevB.63.024201

来源: SCIE

【 摘 要 】

The Coulomb gap in a donor-acceptor model with finite charge-transfer energy Delta describing the electronic system on the dielectric side of the metal-insulator transition is investigated by means of computer simulations on two- and three-dimensional finite samples with a random distribution of equal amounts of donor and acceptor sites. Rigorous relations reflecting the symmetry of the model presented with respect to the exchange of donors and accepters are derived. In the immediate neighborhood of the Fermi energy mu. the single-particle density of states g(epsilon) is determined solely by finite size effects, and g(epsilon) further away from mu is described by an asymmetric power law with a nonuniversal exponent, depending on the parameter Delta.

【 授权许可】

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