The Finite-Difference Time-Domain (FDTD) numerical simulation method has been applied to interpret cathodoluminecence patterns observed for ZnO nanorods grown by a hydrothermal method. The 3D FDTD simulation reproduced the radial electromagnetic field pattern in the hexagonal resonator, corresponding to the CL emission maps of real ZnO microrods. The simulation result for the H _z (TE) polarization—the intense field distribution along edges of the structure, in particular in the corners, but weak in the centre—matched the CL pattern particularly well. Since the experiment was not polarization sensitive, we suppose that polarisation sensitive transmission of electromagnetic field through the ZnO/air interface leads to such an observation. The results of the simulation show also that the lack of axial Fabry-Prot-like resonances in the CL experiments is caused by leaking of the electromagnetic field from the ZnO resonator into the GaN substrate.

有限差分时域（FDTD）数值模拟方法已被用于解释通过水热法生长的ZnO纳米棒观察到的阴极发光图案。3D FDTD仿真再现了六边形谐振腔中的径向电磁场图案，对应于实际ZnO微棒的CL发射图。H _z的仿真结果 （TE）极化-沿结构边缘（特别是在拐角处，但在中心较弱）的强场分布-与CL模式特别匹配。由于该实验对极化不敏感，因此我们认为通过ZnO /空气界面对电磁场的极化敏感传输会导致这种现象。仿真结果还表明，在CL实验中缺少类似Fabry-Prot的轴向共振是由于电磁场从ZnO共振器泄漏到GaN衬底中引起的。