Widely Tunable 2.6 μm GaSb Diode Lasers Utilizing Diffraction Gratings or Silicon Photonics Reflectors

We present two tunable extended cavity laser configurations emitting around 2.6 μm. The gain is provided by a type-I GaSb-based quantum well heterostructure. To demonstrate the high power and broad tuning capabilities of the gain material, an extended cavity laser based on feedback via a diffraction grating is demonstrated. Tuning range of 154 nm, with an average output power of ~10 mW at 2.63 μm, corresponding to a peak power of ~100 mW, is demonstrated. For a more compact and integrable configuration, we demonstrate an extended cavity laser utilizing silicon photonics resonators, where the feedback and tuning is obtained via Vernier effect between two microring resonators. Here, a tuning range of ~70 nm, with an average output power of ~1 mW at 2.55 μm, corresponding to a peak power of ~10 mW, are demonstrated.