Fig. 1. Schematic diagram of the device structure. (a) Structure of epitaxial wafer; (b) structure of traditional MQW; (c) structure of strained-layer MQW

Fig. 2. MQW photoluminescence spectra at different temperatures. (a) Structure of traditional MQW; (b) structure of strained-layer MQW

Fig. 3. MQW photoluminescence spectra peak energies at different excitation power densities. (a) Structure of traditional MQW; (b) structure of strained-layer MQW

Fig. 4. PL spectrum peaks of InGaN strain-layer at different excitation power densities

Fig. 5. EL spectra of two MQWs at injection current of 20 mA