Experimental determination of multiple instability regions by Fourier filtering methods in a single-mirror feedback scheme

Abstract

Summary form only given. Considerable interest emerged in controlling the spatial structures arising spontaneously in nonlinear optical systems by Fourier filtering techniques. In this contribution we utilize a special Fourier filtering scheme to give an experimental demonstration of a basic property of many optical pattern forming systems. This is the existence of a sequence of multiple, tonguelike instability regions at increasing values of transverse wave numbers and a quantitative measurement of their boundaries. The results indicate the origin of a secondary instability in the system without filter occurring far beyond threshold. Also the importance of incorporating finite size effects in the theoretical description for a proper determination of the threshold is demonstrated.