M. Horita et al., WAVELENGTH-TUNABLE INGAASP-INP MULTIPLE-LAMBDA 4-SHIFTED DISTRIBUTED-FEEDBACK LASER/, IEEE journal of quantum electronics, 29(6), 1993, pp. 1810-1816
A wavelength-tunable InGaAsP/InP multiple-lambda/4-shifted distributed
feedback (MQS-DFB) laser was demonstrated for the first time. A DFB l
aser with three lambda/4-shifts and five electrodes was fabricated and
its fundamental characteristics, such as tunability, spectral linewid
th and FM response, were investigated. The stable single mode operatio
n with an excellent SMSR of more than 40 dB was confirmed. Continuous
wavelength tuning under constant output power mode was obtained with a
range of 1.7 nm. Minimum spectral linewidth was 3 MHz at an output po
wer of 20 mW. Flat FM response up to 4 GHz with an efficiency of about
0.65 GHz/mA was also obtained.