Pattern formation in colloids driven by optical single feedback

Single optical feedback systems are considered being versatile models to investigate theoretically and experimentally spontaneous transverse pattern formation, its related bifurcations as well as its dynamics. Stable, controllable transverse patterns were observed in liquid crystal films [1] , atomic vapors [2] , photorefractive crystals [3] and other common nonlinear bulk media. Simple variation of the input power enables investigation of the complete nonlinear scenario from the first bifurcation to the chaotic supercritical regime. Moreover, the natural, inherent access to the Fourier spectrum of an optical system by a lens allows controlling and manipulating of the emerging patterns [4] . The above mentioned advantages of transverse nonlinear optics make investigation of this self-organized phenomenon especially attractive.