Blue and green GaN-based vertical-cavity surface-emitting lasers with AlInN/GaN DBR

We demonstrated a room-temperature continuous-wave (CW) operation of the milliwatt-class single-mode blue and green VCSELs with epitaxially grown AlInN/GaN DBRs on c-plane GaN substrates. The emission wavelength and the threshold current of the blue VCSEL were 442.3 nm and 0.40 mA, respectively. The wall plug efficiency of the blue VCSEL was 13.6%, which is the highest value ever reported. Moreover, stable CW operation beyond 1,000 hours has been confirmed under 0.6 mW at 25 °C. Lasing yield in a 2 in. wafer was more than 80 percent at an average threshold current of 1 mA. Furthermore, we also succeeded in providing high performance green VCSELs. The emission wavelength and the threshold current of the green VCSELs were 514.9 nm and 2.8 mA, respectively. The optical output power was over 1.5 mW and the wall plug efficiency achieved 3.7%, which is the best record for GaN-based green VCSELs. These results will enhance the possibility of the practical use of blue and green VCSELs in the near future.