High-frequency response for DFB LD due to a wavelength detuning effect

A wavelength detuning technique, which intentionally shifts the Bragg wavelength shorter than the gain peak wavelength, has been experimentally confirmed to be effective in improving the frequency response of distributed feedback laser diodes (DFB LD's). A larger differential gain, due to detuning, resulted in a high resonance frequency. A resonance frequency as high as 21 GHz has been achieved in a
\lambda/4
-shift. 1.5-μm DFB-DC-PBH LD with an 80-Å detuning wavelength at 30-mW output power.