Design and Fabrication of Butt-Coupled Sampled Grating DBR Lasers Using Planar Buried Heterostructures

다국어 초록 (Multilingual Abstract)

A butt-coupled (BT) sampled grating distributed Bragg reflector laser diode (SGDBR-LD) was
designed and fabricated using a planar buried heterostructure (PBH), enabling a low threshold
current and a stable fundamental transverse mode. The maximum output power of the fabricated
SGDBR-LD was 24 mW for 200 mA CW operation at 25 C. The measured output power was
14 mW and 13 mW higher than those of a ridged waveguide (RWG) structure and a buried ridge
stripe (BRS). Also, the threshold current was 2 times lower than those of the RWG and the BRS.
Butt-coupled SGDBR-LD’s with target tuning ranges of 44.4 and 63.4 nm were fabricated, and the
tuning ranges were experimentally measured to be 44.4 and 58 nm, respectively. The measured
peak periods of the fabricated SGDBR-LD’s were well matched with theoretical values, and the
output power was close to the calculated values in both cases. The spectrum of 78 channels spaced
by 50 GHz within the tuning range of 35 nm was obtained by using the precise control of the SG
and the phase control currents. A side-mode suppression ratio of more than 35 dB was obtained
over the whole tuning range. The output power variation was less than 5 dB, which is 4 dB smaller
than that of the RWG structure.lEv