Effective-Medium Approximation for Energy-Dependent Hopping on a Lattice
نویسنده
چکیده
We have generalised the standard lattice Coherent-Potential-Approximation (CPA)/EffectiveMedium-Approximation (EMA) scheme to include the case of energy dependent hopping. This case is complicated by the fact that, due to the detailed-balance condition, the hopping rates wij are non-symmetric, i. e. wij 6 wji. Results for the frequency dependent diffusion coefficient are compared with Monte-Carlo simulations for a uniform and bimodal site energy distribution.
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تاریخ انتشار 1999