Surface emitting semiconductor laser achieves efficiency breakthrough

https://phys.org/news/2024-04-surface-emitting-semiconductor-laser-efficiency.html

"20-junction VCSEL power electro-optical conversion room temperature efficiency >88%, multijunction cascaded active area technology reverse tunnel junctions realizing active region cascading, increasing gain volume (15-junction 74%, with slope efficiency 15.6 W/A, corresponding to differential quantum efficiency >1100%)... multiple stimulated emission lowers threshold current... sensing, communication, atomic clocks, optical/quantum computing, topological lasers, medical diagnostics. autonomous driving, AI"