Ohio State University and Sandia National Laboratories in the USA claim the first demonstration of triple-junction cascaded III-nitride light-emitting diodes (LEDs) grown by metal-organic chemical vapor deposition (MOCVD) [Zane Jamal-Eddine et al, Appl. Phys. Express, v14, p092003, 2021]. Stacking LEDs is one way to overcome the limitations in output power density imposed by the effects of efficiency droop at large current density. Tunnel-junction (TJ) structures are used to connect LEDs since they enable electron majority carriers to be transformed to ...