A multi-wavelength laser array where each element can be individually heated for fine tuning. The wavelength of the array can be coarsely tuned by selecting one laser of a particular wavelength for the array, and then applying a heating current to fine-tune the wavelength. The lasers can be phase shifted DFBs for high single-mode yield. The heating can be performed monolithic to the device by passing current longitudinally through the p-type stripe, while the injection current passes vertically through the stripe. Alternatively an adjacent laser to the one selected can be activated, though not fiber coupled, such that the thermal load is sufficient to tune the selected laser. Thin film heaters placed on top or adjacent to the cavity can also be used. To minimize continuous power consumption, the on-chip heater can be used initially to tune the laser while the TE cooler responds on a slower time scale.