title: Parametric spectral correlations in disordered and chaotic structures.
abstract: We explore the influence of external perturbations on the energy levels of a Hamiltonian drawn at random from the Gaussian unitary distribution of Hermitian matrices. By deriving the joint distribution function of eigenvalues, we obtain the (n,m)-point parametric correlation function of the initial and the final density of states for perturbations of arbitrary rank and strength. A further generalization of these results allows for the incorporation of short-range spatial correlations in diffusive as well as ballistic chaotic structures.
authors.affiliation: Cavendish Laboratory, Madingley Road, Cambridge CB3 OHE, United Kingdom.
authors.forename: I E
authors.initials: IE
authors.lastname: Smolyarenko
authors.forename: F M
authors.initials: FM
authors.lastname: Marchetti
authors.forename: B D
authors.initials: BD
authors.lastname: Simons