Electron Microscopy Laboratory, School of Physics, Peking University, Beijing 100871, China.
Opt Lett. 2009 Aug 15;34(16):2533-5. doi: 10.1364/ol.34.002533.
Whispering gallery modes in ZnO nanorods with equilateral triangular cross sections were studied for the first time, to our knowledge. Photoluminescence following excitation with 325 nm radiation was observed at discrete wavelengths and thereby indicated the excitation of whispering gallery modes of triangular ZnO nanorod resonators. These resonances extended over both the visible emission band and the ultraviolet emission band of ZnO. The refractive index of ZnO between 2 eV and 3.2 eV was calculated assuming a "folded" whispering gallery mode and a simple plane-wave model. Our analysis shows that the plane-wave model produces a dispersion curve that agrees well with that of bulk ZnO for large nanorods but shows small deviations when the size of the nanorod resonator approaches the wavelength of the emitted light.
据我们所知，首次研究了等边三角形横截面的 ZnO 纳米棒中的 whispering gallery 模式。在以 325nm 辐射激发后，观察到在离散波长处的光致发光，从而表明了 whispering gallery 模式的激发三角形 ZnO 纳米棒谐振器。这些共振扩展到 ZnO 的可见发射带和紫外发射带。在假设“折叠” whispering gallery 模式和简单平面波模型的情况下，计算了 ZnO 在 2eV 和 3.2eV 之间的折射率。我们的分析表明，平面波模型产生的色散曲线与大纳米棒的体 ZnO 的色散曲线吻合较好，但当纳米棒谐振器的尺寸接近发射光的波长时，会出现较小的偏差。
