STOCHASTIC-EQUATIONS FOR FLUCTUATING POTENTIALS IN DONOR-ACCEPTOR SYSTEMS WITH LOW COMPENSATION

To solve the stochastic equations for fluctuating potentials in donor- acceptor systems with low compensations K, an asymptotic perturbation theory is elaborated and a correction to the Fermi level of impurity e lectrons is calculated: delta mu(K) = c(1)K + c(2)K(3/2) + c(3)K(2) lo g(1/K) + c(4)K(2). The constants c(4) are an asymptotic series in the powers of alpha = 0.23 with coefficients depending on Lambda, where 1/ Lambda is the mean size of the local two-acceptor complex. The constan t c(1) is proportional to Lambda. Thus, despite the dow compensation o f two-acceptor local complexes, their structure determines the leading term of the asymptotic behavior of delta mu(K).