Stabilization of the emission dynamics of a broad area laser by optical feedback

We have experimentally realized a scheme which employs a spatially filtering feedback configuration favoring low-order lateral modes to control the emission dynamics of broad area semiconductor lasers (BALs). We successfully demonstrate stabilization of the spatio-temporal emission dynamics of a BAL with this technique. The results show a substantial suppression of the emission instabilities as compared to the solitary BAL, i.e. without feedback. The measurements were performed using a single-shot streak camera which allows a spatial resolution in one dimension of ∼5 μm, and a temporal resolution down to ∼ 7 ps.