• Demonstrated room-temperature electrically injected lasing in regrowth-free GaN-based photonic-crystal surface-emitting lasers (PCSELs) grown on sapphire substrates.
• Achieved a low threshold current density of 13.7 kA/cm2, indicating efficient device performance.
• The regrowth-free approach simplifies fabrication and reduces cost compared to conventional regrowth methods, while maintaining device quality.
• This work advances GaN-based PCSELs for applications in visible light communication, laser illumination, and other fields requiring compact, high-brightness sources.