title: Laser-induced spatial symmetry breaking in quantum and classical mechanics.
abstract: Phase-controllable transport in laser-irradiated spatially symmetric systems is shown to arise both quantum mechanically and classically from a common field-driven interference mechanism. Specifically, the quantum-to-classical transition for symmetry breaking in a quartic oscillator driven by an omega+2omega field is studied. For this, a double perturbation theory in the oscillator anharmonicity and external field strength, that admits an analytic classical limit, is carried out in the Heisenberg picture. The interferences responsible for the symmetry breaking are shown to survive in the classical limit and are the origins of classical control. Differences between reflection symmetry that plays a key role in the analysis, and parity that does not, are discussed.
authors.affiliation: Chemical Physics Theory Group, Department of Chemistry, and Center for Quantum Information and Quantum Control, University of Toronto, Toronto, Ontario, M5S 3H6, Canada.
authors.forename: Ignacio
authors.initials: I
authors.lastname: Franco
authors.forename: Paul
authors.initials: P
authors.lastname: Brumer