This article demonstrates how to control the behavior of one of the more interesting phenomena in high-power nonlinear optics. Optical filamentation is the collapse of a relatively large optical beam into thin tendrils of propagating light in a medium with a nonlinear optical response. In the right medium, high intensity light produces a self-focusing effect, which leads to more localized and brighter light, and hence more focusing. This reinforcing cycle continues until competing broadening effects form a counterbalance, and narrow bright filaments form.The positioning of these filaments is hard to predict in many standard optical beams, as symmetries are present which make filament locations largely dependent on random perturbations in the beam profile. However, previous publications from this research group have shown how manipulation of the polarization and intensity profile of a laser beam can give predictable and repeatable filament patterns. In this work they significantly extend these results: a wider array of input beam profiles and polarizations are used, and a corresponding broadening of the achievable filamentation patterns is shown. An unprecedented control over the number of filaments and their relative brightness is demonstrated, along with a relaxation in the required symmetries of the propagating pattern. A rigorous prediction/simulation methodology is used, a wide range of examples are given, and the corresponding experimental results show an excellent agreement to predictions. This paper meaningfully expands the potential for the development of new technologies based on optical filamentation.
You must log in
to add comments.