Experimental observation of localization in the spatial frequency domain of a kicked optical system

An experimental realization of an optical "kicked" system is presented. It exhibits localization analogous to that of the quantum "kicked-rotor." In the experiment, free space propagating light is periodically kicked by thin sinusoidal phase gratings, which produce high order diffractions and tend to increase the spatial frequency band. The wave property suppresses this diffusive spread. The localization is realized in a regime near anti-resonance of the system, which is also studied theoretically. The behavior in this regime is similar to that of electronic motion in incommensurate potentials. A crucial part of the experimental system is the grating in-phase positioning, which is done by using the Talbot effect.