Reducing nonideal to ideal coupling in random matrix description of chaotic scattering: application to the time-delay problem.

Fachbereich Physik, Universität-GH Essen, 45117 Essen, Germany.
Physical Review E (Impact Factor: 2.31). 04/2001; 63(3 Pt 2):035202. DOI: 10.1103/PhysRevE.63.035202
Source: arXiv

ABSTRACT We write explicitly a transformation of the scattering phases reducing the problem of quantum chaotic scattering for systems with M statistically equivalent channels at nonideal coupling to that for ideal coupling. Unfolding the phases by their local density leads to universality of their local fluctuations for large M. A relation between the partial time delays and diagonal matrix elements of the Wigner-Smith matrix is revealed for ideal coupling. This helped us in deriving the joint probability distribution of partial time delays and the distribution of the Wigner time delay.

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