Terahertz dual-wavelength quantum cascade laser based on GaN active region

In this paper a novel terahertz (THz) quantum cascade laser (QCL) based on GaN/AlGaN quantum wells has been proposed, which emits at two widely separated wavelengths 33 and 52 μm simultaneously in a single active region. The large LO-phonon energy (∼90 meV), the ultrafast resonant phonon depopulation of the lower radiative levels, suppression of the electrons that escape to the continuum states and selective carrier injection and extraction all together lead to a considerable enhancement in the operating temperature of the structure. All calculations have been done at a temperature of 265 K. Moreover, similar behavior of the output optical powers is another remarkable feature, which makes both wavelengths useful for special applications.

▶ Designed terahertz dual-wavelength quantum cascade laser emits at wavelengths 33 and 52 μm. ▶ We utilize remarkable features of GaN/AlGaN material system. ▶ We improve temperature performance to 265 K by several effective techniques. ▶ Wavelengths are widely separated and have almost similar power behaviors.