The design and operation of integrated dual-wavelength sources are reported. These InGaAs-GaAs ridge waveguide (RW) distributed Bragg reflector (DBR) lasers consist of a common gain section and two, separate DBR sections. Multiple current injection is not necessary for these lasers to operate in dual-wavelength. Dual-wavelength operation is easily achieved by simply biasing the gain section. A relatively low coupling coefficient in the front grating reduces the added cavity loss for the back

more »

... ting mode. Therefore, the back grating mode reaches threshold easily. Also, the addition of a spacing section lowers the current induced thermal interaction between the two uniform grating sections, significantly reducing the inadvertent wavelength drift. As a result, biasing the front DBR section results in tunable mode pair separations (1 ) as small as 0.3 nm and as large as 6.9 nm.