An optical semiconductor device operable in a 0.6 μm band includes an active layer of GaInNP sandwiched by a pair of GaInP layer with a thickness of about 2 molecular layers or less....http://www.google.com/patents/US7198972?utm_source=gb-gplus-sharePatent US7198972 - Laser diode having an active layer containing N and operable in a 0.6 μm wavelength band
