EPL, vol.103, no.3, 2013 (SCI-Expanded)
We investigate quantum tunneling phenomena for an optical lattice subjected to a bichromatic ac force. We show that incommensurability of the frequencies leads to super Bloch oscillation. We propose directed super Bloch oscillation for the quasi-periodically driven optical lattice. We study the dynamical localization and photon-assisted tunneling for a periodical and quasi-periodical ac force. Copyright (C) EPLA, 2013