Nonlinear Analysis of HEMT Inspired GaN Optical Waveguide Under Thermal Stress

We present a study introducing a novel approach to augment nonlinearity within high electron mobility transistor (HEMT) inspired optical waveguides. This study involves the Al-GaN/GaNI AlN layers on both silicon carbide (SiC) and sapphire substrates. Our primary objective is to conduct a comprehensive nonlinear analysis of these structures using the finite element method (FEM) while considering thermal stress. A key aspect of our investigation centers on optimizing light interaction under varying thermal stress conditions. By manipulating core and cladding parameters, we achieve heightened nonlinearity within the temperature range of 27° C to 600° C. Our findings reveal an intriguing outcome: the HEMT inspired waveguide integrated on a sapphire substrate exhibits notably enhanced nonlinearity compared to its SiC substrate counterpart. These results hold significant promise of considering the thermal stress parameter for future on-chip GaN-based quantum photon pair generation applications.