School of Materials Science and Engineering, and Anhui Key Laboratory of Metal Materials and Processing, Anhui University of Technology, Ma-An-Shan, Anhui 243002, People's Republic of China.
Nanotechnology. 2017 May 26;28(21):215205. doi: 10.1088/1361-6528/aa6a38. Epub 2017 Mar 30.
Ultraviolet (UV) surface plasmon (SP) has distinct applications in UV filters, high-density optical storage, spectral enhancement, optical detectors, and nanolithography, which are closely related to plasmon-induced extraordinary optical transmission (EOT). However, such EOT in the UV region has not been the subject of detailed research. We report UV transmission based on theoretical research using the finite-difference time-domain method, by modulating the Al thickness, hole size, array periodicity, and SiO overlayer thickness. It is notable that we can obtain dual-channel UV transmission peaks with excellent qualities such as high transmissivity, zero cross-talk, narrow bandwidth, and perfect symmetry, by optimizing the parameters. The UV transmission peaks have been discovered to non-monotonously shift with increasing hole size. Although array periodicity has great influence on the transmission peak position, the peak energy in the UV region is much less than the value predicted by the well-known periodicity-related surface plasmon polariton (SPP) wavelength equation; the energy discrepancy in the UV region can reach above 20%, which is much larger than the value (typically 4%) in the visible-infrared region. Furthermore, the SiO overlayer may significantly modify the transmission properties. The Al nanohole arrays have also been found to exhibit distinct multi-band UV electric field enhancement properties with special interface effect and size effect. Such extraordinary dual-channel UV transmission with zero cross-talk, based on a very simple Al nanohole array, has promising application in dual-channel UV filters, high-density optical storage, and plasmon-enhanced fluorescence/Raman spectroscopy, which generally involves two wavebands (writing/reading storage or exciting/emission wavelengths). This study is expected to broaden our fundamental understanding of the UV EOT phenomenon, and provide references for experimental research and application of deep-UV and near-UV-related dual-band plasmonic devices.
紫外（UV）表面等离激元（SP）在 UV 滤波器、高密度光存储、光谱增强、光探测器和纳米光刻等方面具有独特的应用，这些应用与等离激元诱导的超常光传输（EOT）密切相关。然而，这种 UV 区的 EOT 尚未得到详细研究。我们通过使用有限差分时域法的理论研究报告了基于 UV 传输，通过调节 Al 厚度、孔大小、阵列周期性和 SiO 覆盖层厚度来实现。值得注意的是，通过优化参数，我们可以获得具有高质量的双通道 UV 传输峰，例如高透过率、零串扰、窄带宽和完美对称。UV 传输峰的位置与孔的大小呈非单调关系。虽然阵列周期性对传输峰位置有很大影响，但 UV 区域的峰值能量远小于著名的与周期性相关的表面等离子体激元（SPP）波长方程所预测的值；在 UV 区域的能量差异可以达到 20%以上，比可见光-红外区域的数值（通常为 4%）大得多。此外，SiO 覆盖层可能会显著改变传输特性。还发现 Al 纳米孔阵列具有特殊的界面效应和尺寸效应，表现出明显的多带 UV 电场增强特性。这种基于非常简单的 Al 纳米孔阵列的非凡双通道 UV 传输具有零串扰特性，在双通道 UV 滤波器、高密度光存储和等离子体增强荧光/Raman 光谱学中具有广阔的应用前景，通常涉及两个波段（写入/读取存储或激发/发射波长）。本研究有望拓宽我们对 UV EOT 现象的基本认识，并为深紫外和近紫外相关双带等离子体器件的实验研究和应用提供参考。
