Investigation on the generation of laser chaos based on dual-mode microsquare laser with optical feedback

We numerically demonstrate the enhancement of chaos bandwidth using a dual-mode microsquare laser under optical feedback. The bandwidth and flatness of the chaotic power spectrum are investigated under different optical feedback rates, mode-frequency intervals and mode intensity differences. Enough feedback strengths, suitable mode-frequency intervals and small mode intensity differences are responsible for wide-band and flat chaotic power spectrum. The results indicate that we can enhance laser chaos by using a laser device with dual-mode lasing.