Electrically Pumped Full-Color and White-Color InGaN/GaN Surface-Emitting Lasers Monolithically Integrated on a Single Chip

摘要标题：照明和显示应用的全色和白色表面发射激光器摘要：非技术：该项目涉及白光和全色表面发射激光器的演示，它们有可能给下一代照明、显示、传感和通信技术带来革命性的变化。到目前为止，还没有有效的半导体激光器工作在深可见(绿色和黄色)光谱范围内，这受到氮化镓材料中存在大密度缺陷的限制。因此，目前商用的绿光激光器一般依赖于非线性光学转换的使用。然而，这种设备体积大、重量重、价格昂贵，不适合芯片上集成。此外，还没有成熟的可制造技术来在同一衬底上空间改变合金成分以实现多色发射。因此，目前的固态灯依赖于使用稀土掺杂的荧光粉来下转换氮化镓发光二极管(LED)的蓝光发射来产生白光，这限制了调节光谱功率分布和实现颜色可调发射的灵活性。在这个项目中，通过使用基于氮化镓的纳米结构，申请者将解决这些根本挑战，并展示小尺寸、高效率的多色激光。该项目将解决半导体发光二极管的绿色缺口，并将实现无磷固态照明，从而显著提高效率，降低制造成本，改善光质量。这项研究的更广泛影响还包括拟议研究的高度跨学科性质，以及对本科生、代表性不足的少数群体和K-12的影响。该项目还提供了教育参与研究的学生和让高中生参与纳米结构材料、LED照明和光子科学技术的机会。技术：申请者提议通过外延、量子限制纳米结构、纳米光子学和器件工程方面的创新来展示白色和全色表面发射激光。通过选择区域外延改变纳米线直径，将在单个芯片上实现全色发射，这是以前氮化镓基量子阱所不可能做到的。此外，非辐射表面复合是纳米线器件的主要限制因素之一，将通过使用纳米线核壳异质结构来解决。在这个项目中，表面发射激光器将利用纳米线光子晶体的二维带边共振效应来实现，而不是使用传统的厚和阻性分布布拉格反射镜。这种独特的方法还将使红色、绿色和蓝色发射器能够在单一芯片上实现单片集成，从而产生以前不可能实现的全色和白色激光二极管。将研究器件特性，包括阈值、壁塞效率、近场和远场分布以及调制特性。

Abstract title: Full-Color and White-Color Surface-Emitting Lasers for Lighting and Display ApplicationsAbstract:Nontechnical: This project is related to the demonstration of white-color and full-color surface-emitting lasers, which have the potential to revolutionize next-generation lighting, display, sensing, and communication technologies. To date, there are no efficient semiconductor lasers operating in the deep visible (green and yellow) spectral range, which has been limited by the presence of large densities of defects in gallium nitride based materials. Consequently, the current commercial green lasers generally rely on the use of nonlinear optical conversion. Such devices, however, are bulky, heavy and expensive, and are not suitable for on-chip integration. Moreover, there has been no established manufacturable technology to spatially vary alloy compositions to achieve multi-color emission on the same substrate. As a result, the current solid-state lamps rely on the use of rare earth doped phosphors to down-convert the blue emission of a gallium nitride based light emitting diode (LED) to generate white-light, which limits the flexibility to tune the spectral power distribution and to achieve color-tunable emission. In this project, by using gallium nitride based nanostructures, the applicant will address these fundamental challenges and demonstrate small size, high efficiency multi-color lasers. This project will address the "green gap" in semiconductor light emitters and will enable phosphor-free solid-state lighting, thereby significantly enhancing the efficiency, reducing the manufacturing cost, and improving the light quality. The broader impacts of this research also include the highly interdisciplinary nature of the proposed research and the outreach to undergraduate, underrepresented minorities, and K-12. This project also provides the opportunity to educate the students involved in the research and to involve high school students on the science and technology of nanostructured materials, LED lighting, and photonics.Technical: The applicant proposes to demonstrate white-color and full-color surface-emitting lasers through innovations in epitaxy, quantum-confined nanostructures, nanophotonics, and device engineering. Full-color emission will be achieved on a single chip by varying the nanowire diameters through selective area epitaxy, which was not previously possible for gallium nitride based quantum wells. Moreover, nonradiative surface recombination, one of the primary limiting factors for nanowire devices, will be addressed by using dot-in-nanowire core-shell heterostructures. In this project, surface-emitting lasers will be achieved by exploiting the two-dimensional band-edge resonant effect of a nanowire photonic crystal, instead of using conventional thick and resistive distributed Bragg reflectors. The unique approach will also enable the monolithic integration of red, green and blue emitters on a single chip, thereby leading to full-color and white-color laser diodes that were not previously possible. The device characteristics, including threshold, wall-plug efficiency, near and far-field profile, and modulation characteristics will be investigated.