Wavelength-tunable three-electrode DBR laser with a thin-active layer in tuning regions

Abstract
A thin-active layer was inserted into the tuning regions of a wavelength-tunable three-electrode DBR (distributed Bragg reflector) laser. The gain of the thin-active layer compensates for the loss in adjacent passive guide layers, and improved the optical output power and spectral linewidth in tuning operations. The total tuning range was over 8 nm and the continuous tuning range was over 1 nm, with an output power increase of 30%.