EFFECT OF STRONG OPTICAL FEEDBACK ON VERTICAL-CAVITY SURFACE-EMITTINGLASERS

An analysis is performed of the effects of strong optical feedback on the characteristics of single-transverse mode VCSEL's, Consideration i s given to the cases of short (1.5 cm) and long (15 cm) external cavit ies. When the laser is operated well above threshold in a short extern al cavity with high reflectivity, a strong dependence on the accumulat ed external cavity phase is observed. Stable operation is found for an optimum phase while for other values of the phase chaotic dynamics is observed, Such behavior Is not seen near threshold where the laser ou tput is stable for any accumulated phase. For the longer external cavi ty the influence of the phase term is found to be insignificant: chaot ic behavior is seen in the output over a wide range of operating curre nts.