Widely tunable dual-mode distributed feedback laser fabricated by selective area growth technology integrated with Ti...

A widely tunable dual-mode distributed feedback (DFB) laser fabricated by selective area growth (SAG) technology integrated with Ti heaters was demonstrated. In the device, an original mode spacing of 4 nm was obtained by the simple SAG technology. Ti thin-film heaters were integrated with a novel procedure, which simplifies the fabrication of such heaters greatly. A large electrical resistance of the heaters is obtained at the same time, resulting in a high wavelength tuning efficiency. An accurate mode spacing as small as 0.34 nm and as large as 8.06 nm is achieved, which corresponds to a wide beat frequency range from 42.2 GHz to 1 THz. The simple fabrication process indicates that it is promising for reducing the cost of dual-mode DFB laser in fabricating self-pulsation lasers and THz generators.