High-Indium-content nonpolar quantum wells for green, yellow, and red light emitters

缺乏对偏振场的控制是目前限制iii -氮化物异质结构在绿色和更长波发光器件（包括绿色激光二极管）中应用的主要因素。通过使用非极性取向来控制偏振场，我们的目标是为更好的可见光发射器打开大门。非极性异质结构的外延生长将研究和优化低缺陷密度，突然界面和均匀成分。重点是具有高铟含量的GaInN量子阱，适合绿色和更长的波长应用。关键是要控制铟掺入量超过30%，以保持完全的晶格匹配以及完全均匀和随机生长。时间分辨光谱学和光增益光谱学揭示了非辐射复合损失的影响，既有缺陷，也有本征复合。通过共振光电流噪声光谱法获得缺陷等级的直接信息。与研究小组的伙伴合作，将非极性方法与半极性和极性方法进行比较。

The lack of control of polarization fields is presently a major factor limiting application of III-nitride based heterostructures for green and longer wavelength light-emitting devices, including green laser diodes.By controlling polarization fields through the use of non-polar orientations we aim at opening the door for better visible light emitters. Epitaxial growth of non-polar heterostructures will be studied and optimized for low defect densities, abrupt interfaces and homogeneous compositions. The emphasis is on GaInN quantum wells with high Indium content suited for green and longer wavelength applications. As a key, Indium incorporation beyond 30% needs to be controlled maintaining full lattice-matching as well as fully homogeneous and stochiometric growth.Time-resolved optical spectroscopy as well as optical gain spectroscopy reveal the influence of nonradiative recombination losses, both due to defects and to intrinsic recombination. Direct information about defect levels is obtained through resonant photocurrent noise spectroscopy. In collaboration with partners from the Research Group, the non-polar approach will be compared to the semipolar and the polar approach.