Institute for Advanced Studying, School of Materials Science and Engineering, Nanchang University, Nanchang, People's Republic of China.
Nanotechnology. 2010 Jan 15;21(2):025704. doi: 10.1088/0957-4484/21/2/025704. Epub 2009 Dec 3.
In ZnO hierarchical heterostructures of zinc antimonate nanoislands on ZnO nanobelts, the substitution of Sb(5+) for Zn(2+) induces lattice contraction and a variation in vacancy defects, and moreover the preferential accumulation and segregation of Sb in [001] planes results in the intense perturbation of atomic motion in the a-b plane. Under nonresonant conditions, nonpolar E(2)(high) and polar quasi-longitudinal optic (LO) modes decrease in frequency due to finite-size and phonon confinement effects. Under resonant conditions, localized excitons can ionize to free carriers and form plasmons at higher excitation power density, resulting in the transformation of scattering coupling from localized exciton-LO-phonon to LO-phonon-plasmon. The intensity ratio of 2LO/1LO decreases and multiphonon scattering shows a decrease in frequency with unequal neighboring interval, and moreover the scattering coupling between the continuum of electron-hole plasmon and the discrete LO phonons causes an asymmetric lineshape.
在 ZnO 纳米带负载的锌锑酸盐纳米岛的 ZnO 分级异质结构中，Sb(5+)取代 Zn(2+)会引起晶格收缩和空位缺陷的变化，此外 Sb 在 [001] 面的优先聚集和分凝会导致 a-b 面原子运动的强烈扰动。在非共振条件下，非极性 E(2)(高)和极性准纵光学 (LO) 模由于有限尺寸和声子限制效应而频率降低。在共振条件下，局域激子可以离化到自由载流子，并在更高的激发功率密度下形成等离子体，从而导致散射耦合从局域激子-LO 声子转变为 LO 声子-等离子体。2LO/1LO 的强度比减小，多声子散射的频率随不等邻域间隔而减小，此外，电子-空穴等离子体连续谱与离散 LO 声子之间的散射耦合导致不对称线宽。
