Department of Physics, Tohoku University, 980-8578 Sendai, Japan.
Opt Lett. 2012 Jul 15;37(14):2793-5. doi: 10.1364/OL.37.002793.
We carried out an experimental and numerical investigation of photoinduced voltage at normal incidence in the nondiffraction regime, which was not predicted to occur by the simple momentum conservation model. We prepared two samples: one having space inversion symmetry and the other without this feature. At normal incidence in the nondiffraction regime, we observed a finite signal only for the asymmetric structure. We found that surface plasmon polaritons (SPPs) are excited by the signal and are attributed to the origin of the voltage. We also evaluated the radiation force of light by using the Maxwell stress tensor and found that pressure of light and not shear force is mainly induced in the structure due to the asymmetric excitation of SPPs.
我们进行了一项实验和数值研究，探究了在非衍射区域内正常入射时光致电压的现象，这一现象无法用简单的动量守恒模型来预测。我们制备了两个样品：一个具有空间反转对称性，另一个则没有这个特征。在非衍射区域内正常入射时，我们仅观察到非对称结构会产生有限的信号。我们发现，表面等离激元（SPP）被信号激发，这是电压产生的原因。我们还通过麦克斯韦应力张量评估了光的辐射力，发现由于 SPP 的非对称激发，主要是光的压力而不是剪切力引起结构中的光压。
