Suppression of optical field leakage to GaN substrate in GaN-based green laser diode

In this study, n-InGaN and u-InGaN are proposed to be the lower waveguide (LWG) and quantum barrier (QB), respectively, to eliminate the leakage of optical field to GaN substrate in GaN-based green laser diode (LD). The optical and electrical characteristics of LDs are calculated by the economic software LASTIP, and it is found that the leakage of optical field is suppressed significantly and the threshold current is also reduced. Further theoretical analysis shows that n-In0.08Ga0.92N LWG and u-In0.02Ga0.98N QB is effective to concentrate the optical field and to enhance optical confinement for our green LDs, leading to an improvement of optical and electrical performance of green LDs.