First demonstration of 1.3 μm quarter-wavelength shift distributed feedback (DFB) semiconductor laser based on conventional photolithography

A 1.3 μm distributed feedback (DFB) semiconductor laser with equivalent λ/4 phase shift based on reconstruction equivalent chirp (REC) technique is numerically studied and experimentally demonstrated. The simulation results show that the 1.3 μm DFB laser with equivalent λ/4 phase shift based on the REC technique performs the same as that of actual λ/4 phase shift DFB laser, with nearly the same P-I curves, the internal power distributions and the output ASE spectra. Compared with the traditional λ/4 phase shift DFB laser, the REC based laser only changes the sampling structures with the uniform seed waveguide grating instead of the actual grating structures. As a result, the fabrication of such laser will be very easy. In this paper, we successfully fabricated the 1.3 μm DFB laser based on the REC technique for the first time to the best of our knowledge.