Diverse classical walking of a single atom in an amplitude-modulated standing wave lattice

The classical walking behaviors of a single atom in an amplitude-modulated standing wave lattice beyond the internal dynamics are investigated. Based on a simple effective model, we identify a diversity of dynamic regimes of atomic motion by periodically adjusting the lattice depth. Harmonic oscillation or pendulum rotation with classical step-jumping, random scattering walking, chaotic transportation, quasi-periodic trapped motion and roughly ballistic free flying are found in this simple model within different parametric regions by approximate analyses. Our study demonstrates a complex motion of single atom in modulating optical lattice beyond the quantum description.