InP-Based Type-II Quantum-Well Lasers and LEDs

Type-II InP-based light sources provide a promising concept for mid-infrared lasers. These have recently made huge progress, as the first electrically and optically pumped lasers could be demonstrated beyond the wavelength limit for type-I InP-based lasers (~2.3 μm). In this paper, we introduce the material system and device concepts, and report the latest achievements, such as electrically pumped lasing operation up to a wavelength of 2.6 μm in pulsed mode, continuous-wave resonant-cavity light-emitting diode operation up to a wavelength of 3.3 μm at 20-80 °C and photoluminescence even up to 3.9 μm.