Monolithic DWDM source with precise channel spacing

Abstract We report a low-cost manufacturing approach for fabricating monolithic multi-wavelength sources dense wavelength division multiplexing (DWDM) systems that offers high yield and eliminates crystal regrowth selective area epitaxy steps are essential in traditional fabrication methods. The source integrates an array of distributed feedback (DFB) lasers with passive coupler semiconductor optical amplifier (SOA). Ridge waveguide sampled Bragg side wall gratings have been integrated using quantum well intermixing to achieve fully functional four-channel DWDM 0.8 nm spacing residual errors < 0.13 nm. output power from the SOA is > 10 mW per channel making suitable use networks (PONs). also investigated multisection phase-shifted both increase effective grating coupling coefficient precisely control lasing spacing. An 8-channel DFB laser 100 GHz was demonstrated two π -phase-shifted sections each sampling period. entire fabricated by only single step electron beam lithography.