Disentangling the effects of nanoscale structural variations on the light emission wavelength of single nano-emitters: InGaN/GaN multiquantum well nano-LEDs for a case study.
Disentangling the effects of nanoscale structural variations on the light emission wavelength of single nano-emitters: InGaN/GaN multiquantum well nano-LEDs for a case study.
复制标题
DOI：
10.1039/c4nr02939a
复制
发表时间：
2014-09
期刊：
影响因子：
6.7
通讯作者：
G. Sarau;M. Heilmann;M. Latzel;S. Christiansen
中科院分区：
文献类型：
--
作者：
G. Sarau;M. Heilmann;M. Latzel;S. Christiansen
半导体纳米发射器的光发射波长中的散射被分配给应变、厚度和组成的纳米级变化，这在从高效光源到光致发光的当前和新型纳米技术中是关键的。在这里，我们提出了一个相关的实验和理论研究的基础上InGaN/GaN多量子威尔斯阱的单纳米棒发光二极管（nano-LED）分离这些本征波动的贡献。阴极发光测量表明，具有相同的应变状态的纳米LED探测非共振显微拉曼光谱可以辐射不同波长的光。在测量的光学跃迁的偏差同意非常好的量子阱厚度为2.07-2.72 nm和在17.5-19.5%的分数紧密包围的增长值的带轮廓计算。纳米棒的表面粗糙度控制表面光学声子模式的外观与声子辅助纳米LED器件的设计上的直接影响。这项工作建立了一个新的，简单的，和强大的方法，基本的理解，以及定量分析的应变-光发射关系和表面相关的现象，在新兴领域的纳米发射器。
The scattering in the light emission wavelength of semiconductor nano-emitters assigned to nanoscale variations in strain, thickness, and composition is critical in current and novel nanotechnologies from highly efficient light sources to photovoltaics. Here, we present a correlated experimental and theoretical study of single nanorod light emitting diodes (nano-LEDs) based on InGaN/GaN multiquantum wells to separate the contributions of these intrinsic fluctuations. Cathodoluminescence measurements show that nano-LEDs with identical strain states probed by non-resonant micro-Raman spectroscopy can radiate light at different wavelengths. The deviations in the measured optical transitions agree very well with band profile calculations for quantum well thicknesses of 2.07-2.72 nm and In fractions of 17.5-19.5% tightly enclosing the growth values. The nanorod surface roughness controls the appearance of surface optical phonon modes with direct implications on the design of phonon assisted nano-LED devices. This work establishes a new, simple, and powerful methodology for fundamental understanding as well as quantitative analysis of the strain - light emission relationship and surface-related phenomena in the emerging field of nano-emitters.