Electrically pumped green lasing action from InGaN/GaN MQW heterojunction with a p-NiO cap layer

Electrically pumped green lasing action has been achieved from an In0.23Ga0.77N/GaN multi quantum well heterojunction with a p-NiO cap layer. The NiO epilayer grown by photo-assisted metal organic chemical vapor deposition (MOCVD) showed high crystal quality with cubic NaCl morphological structure. Under forward bias, distinct diode rectification characteristics were obtained and the turn-on voltage was about 2.0 V. Increasing the current to 30 mA, strong sharp lasing peaks with narrower line width of 0.8 nm was detected. The lasing mechanism and current transport of the diode were studied through the aspects of energy band structure of the diode.