DISSIPATIVE TRANSPORT IN DC-AC-DRIVEN TIGHT-BINDING LATTICES

We investigate the incoherent dissipative quantum transport of a parti cle in a periodic lattice being driven nonlinearly by dc-ac fields. Th e particle always diffuses slower, as compared to the force-free case, and the minimal diffusion is found for zero de-bias and ac-field para meters that lead to dynamical localization (DL) in the nondissipative case. A current inversion occurs at weak dissipation. The amplitude of the negative current is maximal for a characteristic value of the dis sipative strength, resembling a ''stochastic resonance'' like effect. For intermediate dissipation the current is positive and widely indepe ndent of both the ac-frequency and the dissipation. The negative curre nt, as well as the stability of DL against dissipation are universal e ffects, in the sense that they are largely independent of the dissipat ive mechanism.