Dynamical origin of decoherence in classically chaotic systems

The decay of the overlap between a wave packet evolved with a Hamiltonian H and the same state evolved with H+Σ serves as a measure of the decoherence time τφ. Recent experimental and analytical evidence on classically chaotic systems suggest that, under certain conditions, τφ depends on H but not on Σ. By solving numerically a Hamiltonian model we find evidence of that property provided that the system shows a Wigner–Dyson spectrum (which defines quantum chaos) and the perturbation exceeds a crytical value defined by the parametric correlations of the spectra.