An analysis of the second-order nonlinear polarizability of III-V, -oriented heterostructures is presented. This analysis is used as a basis for the discussion of visible second-harmonic light-emitters. It is then shown experimentally that active blue-green light-emitters can be fabricated from (In,Ga)As/GaAs quantum well laser structures.
P. A. Ramos,
"Active (In,Ga)As/GaAs blue-green light emitters", Proc. SPIE 3001, In-Plane Semiconductor Lasers: from Ultraviolet to Midinfrared, (2 May 1997); doi: 10.1117/12.273785; https://doi.org/10.1117/12.273785