Suppression of quantum coherence: Noise effect Original Research Article

The influence of noise on the tunneling dynamics in a periodically driven two-level system is discussed. To describe the noisy quantum dynamics the stochastic Schrödinger equation is used. It accounts for the mutual influence of both phase damping and circularly polarized field driving with a noisy amplitude. It is shown that in absence of deterministic driving, a random dynamic drive stabilizes the localized state while a random, non-demolition drive (see below) destabilizes the localized state. In contrast, localization which can be induced by deterministic driving fields is destroyed by either phase damping or fluctuations of the driving fields. The delocalization rate for intermediate-to-strong field strength turns out to be universal. Approximate results can be obtained by a perturbation treatment.