The authors report a wavelength tunable laser consisting of an in-line Fabry-Perot laser and lateral-grating assisted vertical codirectional coupled filter. The device can be tuned over 12 discrete 4 nm spaced longitudinal modes giving a total tuning range of 44 nm.

The authors report a grating assisted vertical coupler filter laser that uses a novel lateral grating to provide coupling vertically between the guides. This approach simplifies device fabrication. A wavelength tuning range of 58nm is reported.