Knab J R, Adam A J L, Nagel M, Shaner E, Seo M A, Kim D S, Planken P C M
Delft University of Technology, Faculty of Applied Sciences, Department of Imaging Science and Technology, Optics Research Group, Lorentzweg 1, 2628 CJ Delft, The Netherlands.
Opt Express. 2009 Aug 17;17(17):15072-86. doi: 10.1364/oe.17.015072.
We present measurements of the complete terahertz (THz) electric near-field distribution, E(x), E(y) and E(z), in both the time- and frequency-domains, for subwavelength apertures and subsections of subwavelength aperture arrays. Measuring the individual components of the THz near-field with subwavelength spatial resolution, as they emerge from these structures, illustrates how the field interacts with the apertures. We observe the small but measurable y- and z-components of the electric field for both single apertures and arrays. Resonant contributions, attributed to Bloch modes, are detected and we observe the presence of a longitudinal field component, E(z), within the different array apertures, which can be attributed to a diffractive effect. These measurements illustrate in detail the individual THz field components emerging from subwavelength apertures and provide a direct measure of two important mechanisms that contribute to the net transmission of light through arrays.
我们展示了在时域和频域中，针对亚波长孔径以及亚波长孔径阵列的各部分，对完整太赫兹（THz）电近场分布E(x)、E(y)和E(z)的测量结果。以亚波长空间分辨率测量这些结构产生的太赫兹近场的各个分量，说明了场与孔径的相互作用方式。我们观察到，对于单个孔径和阵列，电场的y分量和z分量虽小但可测量。检测到了归因于布洛赫模式的共振贡献，并且我们观察到在不同的阵列孔径内存在纵向场分量E(z)，这可归因于衍射效应。这些测量详细说明了从亚波长孔径中出现的各个太赫兹场分量，并直接测量了有助于光通过阵列进行净传输的两个重要机制。
