Optical Properties of Staggered InGaN/InGaN/GaN Quantum-Well Structures with Ga- and N-Faces

Optical properties of staggered InGaN/InGaN/GaN quantum-well (QW) light-emitting diodes with Ga- and N-faces were investigated using the multiband effective mass theory. The staggered QW structure shows that the carrier density dependence of the transition wavelength is largely reduced compared to the conventional QW structure. On the other hand, the heavy-hole effective mass around the topmost valence band is almost unaffected by the polarity. The N-face staggered InGaN/InGaN/GaN QW structure has a greater spontaneous emission peak than the Ga-face staggered InGaN/InGaN/GaN QW structure because the former has a larger matrix element than the latter. We expect the N-face staggered InGaN/InGaN/GaN QW structure to have improved characteristics compared with the Ga-face staggered InGaN/InGaN/GaN QW structure.