60 mW continuous-wave operation of InGaN laser diodes made by plasma-assisted molecular-beam epitaxy

We demonstrate continuous-wave operation at 411nm of InGaN multi-quantum-well laser diodes (LDs) made by plasma-assisted molecular-beam epitaxy (PAMBE). The threshold current density and voltage for these LDs are 4.2kA∕cm2 and 5.3V, respectively. High optical output power of 60mW is achieved. The LDs are fabricated on low-dislocation-density bulk GaN substrates, at growth conditions which resemble liquid-phase epitaxy. We show that use of such substrates eliminates spiral growth, which is the dominant growth mechanism for PAMBE on high-dislocation-density substrates. Therefore, PAMBE opens new perspectives for next generation of InGaN LDs.