Non-Hermiticity in a kicked model: decoherence and the semiclassical limit.

We study the effects of non-Hermitian perturbations on a quantum kicked model exhibiting a localization transition. Using an exact renormalization scheme, we show that the critical line separating the extended and localized phases approaches its semiclassical limit as the imaginary part of the kicking parameter is steadily increased. Further, the metastability of the quantum states appears to be directly correlated with the deviation between the semiclassical and quantum results. This direct evidence of quantum-classical correspondence suggests that decoherence may be usefully modeled by non-Hermitian perturbations.