Abstract

We have experimentally studied the influence of a long external cavity on the spatiotemporal emission-characteristics of broad area semiconductor lasers. We have measured the intensity of the nearfield time-resolved and time-integrated. The dynamics within the time-integrated filaments has been detected with a fast avalanche photodiode-array. From its signals we have taken power spectra and time series on a ns time scale. From the time series we have calculated cross-correlation coefficients to caracterizo the spatio-temporal behavior. Figure 1 shows the nearfield of a gain-guided semiconductor laser in the one-to-one feedback-image configuration. With increasing feedback the dynamics becomes more complex as can be seen from the intensity spectra (fig.2). Simultaneously the correlation over the width changes to negative values(fig.3).

© 1996 IEEE