Modulation characteristics of constricted double-heterojunction AlGaAs laser diodes

Detailed experimental results are presented for three types of constricted double-heterojunction (CDH) AlGaAs laser diodes. The dynamic properties (pulsed and RF modulation, noise response, and linearity characteristics) of these devices are given for the first time. Performance in analog and digital signal transmission systems is also described for the most useful types of such devices: the standard CDH [1], [2] and the high-power CDH large optical cavity (LOC) [3], [4]. With the latter, an order-of-magnitude increase in modulated power capability over standard devices has been achieved (40-mW peak power into 0.2 NA, 50-μm core graded-index fiber). Finally, we present a detailed experimental analysis of self-oscillation phenomena in a variant type of CDH structure (CDH-AMC) (asymmetric mode confinement) [5]. These observations, although uncommon in CDH and CDH-LOC devices, provide new experimental insight on the nature of self-pulsating laser diodes.