Abstract
The net modal gain of the InGaN/GaN multiple quantum well has been measured by the variable excitation stripe length method for an optically pumped cavity along each crystal orientation on the (0001) plane. These results demonstrated the theoretical prediction of the fact that the maximum optical gain can be obtained at a [1210]-oriented edge-emitting laser cavity, which has been reported in the literature. "Crystal orientation" is confirmed to be a related parameter to the optical gain for a GaN-based strained structure. © 2001 American Institute of Physics.