Y. Tohmori et al., BROAD-RANGE WAVELENGTH-TUNABLE SUPERSTRUCTURE GRATING (SSG) DBR LASERS, IEEE journal of quantum electronics, 29(6), 1993, pp. 1817-1823
A broad-range tuning is demonstrated in tunable DBR lasers with a newl
y proposed superstructure grating (SSG). These SSG reflectors were fab
ricated by electron-beam lithography, and a grating performance was ev
aluated by measuring the transmittance characteristics of the ridge-ty
pe SSG reflector. Incorporating this SSG reflector into DBR lasers res
ults in wavelength-tunable lasers that can cover a wide-wavelength ran
ge by using coarse and fine tuning mechanisms. Wavelength-tunable SSG
DBR lasers were fabricated and operated under low-threshold CW conditi
ons. Wavelength tuning ranges of 50 and 100 nm were designed and exper
imentally measured to be 50 and 83 nm, respectively, with single-mode
operation. In devices with a 100 nm tuning range, 103 nm tuning was ac
hieved for the first time by including a multimode-wavelength region.
The temperature dependence and modulation characteristics of these las
ers are stable over their wide tuning range.