Demonstration of phosphor-free polarized white light emission from monolithically integrated semipolar InGaN quantum wells

We report a device design that monolithically integrates an electrically injected blue light-emitting diode grown on the (202¯1¯) face of a bulk GaN substrate and yellow emitting optically pumped InGaN quantum wells (QWs) grown on the (202¯1) face. Emission peaks are observed at 440 nm and 560 nm from the electrically injected and optically pumped QWs, respectively. The ratio of blue to yellow light can be optimized to result in polarized white light emission from this phosphor-free device. We demonstrate emission with Commission Internationale de l'Eclairage x- and y-chromaticity coordinates of (0.28, 0.29) and an optical polarization ratio of 0.40.