531 nm Green Lasing of InGaN Based Laser Diodes on Semi-Polar {20(2)over-bar1} Free-Standing GaN Substrates

Lasing in pure green region around 520nm of InGaN based laser diodes (LDs) on semi-polar [20 (2) over bar1) free-standing GaN substrates was demonstrated under pulsed operation at room temperature. The longest lasing wavelength reached to 531 nm and typical threshold current density was 8.2 kA/cm(2) for 520 nm LDs. Utilization of a novel {20 (2) over bar1} plane enabled a fabrication of homogeneous InGaN quantum wells (QWs) even at high In composition, which is exhibited with narrower spectral widths of spontaneous emission from LDs than those on other planes. The high quality InGaN QWs on the {20 (2) over bar1} plane advanced the realization of the green LDs. (C) 2009 The Japan Society of Applied Physics