MAGNETOCONDUCTANCE AUTOCORRELATION FUNCTION FOR FEW-CHANNEL CHAOTIC MICROSTRUCTURES

Using the Landauer formula and a random matrix model, we investigate t he autocorrelation function of the conductance versus magnetic field s trength for ballistic electron transport through few-channel microstru ctures with the shape of a classically chaotic billiard coupled to ide al leads. This function depends on the total number M of channels and the parameter t which measures the difference in magnetic field streng ths. Using the supersymmetry technique, we calculate for any value of M the leading terms of the asymptotic expansion for small t. We pay pa rticular attention to the evaluation of the boundary terms. For small values of M, we supplement this analytical study by a numerical simula tion. We compare our results with the squared Lorentzian suggested by semiclassical theory and valid for large M. For small M, we present ev idence for non-analytic behavior of the autocorrelation Function at t = 0. (C) 1998 Academic Press.