Quantum diffusion in the Harper model under polychromatic time-perturbation
Phys. Rev. E 113, 014211 – Published 20 January, 2026
DOI: https://doi.org/10.1103/768k-ghzl
Abstract
Quantum dynamics of the Harper model with self-duality exhibits localized, diffusive, and ballistic states depending on the potential strength . By adding time-dependent harmonic perturbations composed of incommensurate frequencies, we show that all states of the Harper model transition to quantum diffusive states as the perturbation strength increases for . The transition schemes and diffusion behaviors are discussed in detail and the phase diagram in the parameter space is presented.