Electromagnetic enhancement effect in scanning tunneling microscope light emission from GaAs
Electromagnetic enhancement effect in scanning tunneling microscope light emission from GaAs
复制标题
DOI：
10.1063/1.1554473
复制
发表时间：
2003-03
影响因子：
3.2
通讯作者：
Y. Uehara;H. Gotoh;R. Arafune;S. Ushioda
中科院分区：
文献类型：
--
作者：
Y. Uehara;H. Gotoh;R. Arafune;S. Ushioda
用时域有限差分法研究了GaAs的扫描隧道显微镜（STM）发光的电磁增强效应。我们已经计算了由少数载流子注入的尖端和样品中的多数载流子的复合所发射的光的强度。结果不仅取决于针尖的材料和形状，而且取决于光的偏振。当尖端是钨，其介电函数在1.5 eV处具有正的真实的部分时，p偏振光强度强烈地依赖于尖端的尺寸和复合的位置。然而，s-偏振光发射仅微弱地依赖于这些参数。如果针尖是一个完美的金属，p偏振光强度变得比相同形状的W针尖强几倍。另一方面，由于理想金属的电磁屏蔽效应，s偏振光强度变得比W尖端弱。我们得出结论，组合或…
The electromagnetic enhancement effect in scanning tunneling microscope (STM) light emission from GaAs has been investigated by the finite difference time domain method. We have calculated the intensity of light emitted by the recombination of minority carriers injected from the tip and majority carriers in the sample. The results depend not only on the material and the shape of the tip but also on light polarization. When the tip is tungsten whose dielectric function has a positive real part at 1.5 eV, the p-polarized light intensity depends strongly on the size of the tip and the location of recombination. However, the s-polarized light emission depends only weakly on these parameters. If the tip is a perfect metal, the p-polarized light intensity becomes a few times stronger than that for the W tip of the same shape. On the other hand, the s-polarized light intensity becomes weaker than that for the W tip due to the electromagnetic screening effect of a perfect metal. We conclude that the combination o...