A Dual-Wavelength DFB Laser Based on Reconstruction-Equivalent-Chirp Technology for Millimeter-Wave Generation

A monolithic integrated dual-wavelength distribute feedback (DFB) laser with equivalent apodized sampling Bragg grating (SBG) is proposed in this paper. The simulation results show that such a grating structure possesses dual-wavelength narrow transmission peaks in +1st channel and the wavelength spacing between the two lasing modes can be designed from 56 GHz to 103 GHz by varying the cavity length. Utilizing the reconstruction-equivalent-chirp (REC) technique, the apodization is achieved by modulating the duty cycle of SBGs. The grating structure of the laser can be fabricated by holographic exposure combined with conventional lithography.