Localized Laser Recrystallization as an Alternative Route to High-Efficiency Red InGaN Nanowires

High-efficient red emission in III-nitride semiconductors remains a significant challenge due to crystal degradation caused by high In content and non-radiative recombination. In this study, we propose a 405 nm laser-induced re-crystallization (Re-Cryst) process to enhance the optical performance of 665 nm red-emitting core-shell InGaN/GaN nanowires grown by metal-organic chemical vapor deposition. Unlike conventional thermal annealing, this laser-based approach enables localized defect healing and improved lattice ordering while minimizing In decomposition. Micro-photoluminescence measurements revealed a 1.92-fold increase in band edge emission intensity at a shifted peak wavelength of 624 nm, attributed to strain relaxation and partial In decomposition. To evaluate the improvement in radiative recombination, we introduce a new figure of merit, referred to as the Radiative-PL-Rate (R_RPL), which is defined as the rate of PL intensity at low excitation to that at saturation. The R_RPL increased from 6.21% in the as-grown sample to 11.59% in the Re-Cryst sample, indicating a substantial suppression of non-radiative recombination. Furthermore, we demonstrated the mechanisms behind improved crystal quality and radiative efficiency, showing that the Re-Cryst process selectively heals defects, enhances red emission, and advances high-performance micro-displays for next-generation AR/VR applications.