2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/23711Objects driven through periodically modulated potential-energy landscapes in two dimensions can become locked in to symmetry-selected directions that are independent of the driving force's orientation. We investigate this problem in the overdamped limit, and demonstrate that the crossover from free-flowing to locked-in transport can depend exponentially on an object's size, with this exceptional selectivity emerging from the periodicity of the environment.11 pages, 6 figures, RevTeX4Soft Condensed Mattertext