High-Performance AlGaN-Based UV-A Laser Diodes With Polarization-Modulated Superlattice Hole Injection and a Graded Electron-Blocking Layer

Le résumé fourni par la source

Carrier imbalance—characterized by an electron-rich active region caused by limited hole injection—has long been a major challenge for AlGaN-based UV-A laser diodes, severely degrading their optoelectronic performance. In this work, we investigate AlGaN-based UV-A laser diodes emitting at approximately 358 nm and propose a hybrid design that combines a thin-well p-AlGaN/GaN superlattice hole-injection layer with a compositionally graded AlGaN electron-blocking layer (EBL) to simultaneously enhance hole injection and suppress electron leakage, thereby restoring electron-hole injection balance and improving carrier transport. Numerical simulations demonstrate that the superlattice markedly reduces the polarization-induced electric field near the EBL, alleviating interfacial carrier accumulation and boosting the local hole concentration in the p-type region by more than two orders of magnitude. Moreover, the graded EBL provides improved barrier modulation, suppressing electron leakage while facilitating hole injection, thereby enhancing the radiative recombination rate. Compared with the conventional structure with fixed compositions, the output optical power increases by 240%, and the wall-plug efficiency increases by 386.2%. These results suggest a promising strategy for achieving highly efficient hole injection in AlGaN-based UV-A laser diodes.

Ce résumé expose les affirmations des auteurs. BNTIC ne l’interprète pas comme une validation indépendante des résultats.