Blue and aquamarine stress-relaxed semipolar (11(2)over-bar2) laser diodes

Strain compensated AlGaN/InGaN superlattice electron/hole blocking layers were utilized in semipolar (11 (2) over bar2) laser diodes grown on intentionally stress-relaxed n-InGaN waveguiding layers. The use of an AlGaN/InGaN superlattice instead of a single compositional layer of AlGaN suppressed the formation of misfit dislocations at the electron/hole blocking layer heterointerfaces. Using this design, lasing at 447 nm was achieved with a threshold current density of 7.2 kA/cm(2), which is remarkably lower than previous results. Furthermore, we demonstrate a 497 nm aquamarine-emitting semipolar (11 (2) over bar2) laser diode under pulsed operation. (C) 2013 AIP Publishing LLC.