Khosroabadi Akram A, Gangopadhyay Palash, Hernandez Steven, Kim Kyungjo, Peyghambarian Nasser, Norwood Robert A
College of Optical Sciences, the University of Arizona, Tucson 85721, AZ, USA.
Materials (Basel). 2015 Aug 7;8(8):5028-5047. doi: 10.3390/ma8085028.
We present a proof of concept for tunable plasmon resonance frequencies in a core shell nano-architectured hybrid metal-semiconductor multilayer structure, with Ag as the active shell and ITO as the dielectric modulation media. Our method relies on the collective change in the dielectric function within the metal semiconductor interface to control the surface. Here we report fabrication and optical spectroscopy studies of large-area, nanostructured, hybrid silver and indium tin oxide (ITO) structures, with feature sizes below 100 nm and a controlled surface architecture. The optical and electrical properties of these core shell electrodes, including the surface plasmon frequency, can be tuned by suitably changing the order and thickness of the dielectric layers. By varying the dimensions of the nanopillars, the surface plasmon wavelength of the nanopillar Ag can be tuned from 650 to 690 nm. Adding layers of ITO to the structure further shifts the resonance wavelength toward the IR region and, depending on the sequence and thickness of the layers within the structure, we show that such structures can be applied in sensing devices including enhancing silicon as a photodetection material.
我们展示了一种在核壳纳米结构混合金属 - 半导体多层结构中实现可调谐等离子体共振频率的概念验证，其中以银作为活性壳层，氧化铟锡作为介电调制介质。我们的方法依赖于金属 - 半导体界面内介电函数的集体变化来控制表面。在此，我们报告了大面积、纳米结构的银与氧化铟锡（ITO）混合结构的制备及光谱学研究，其特征尺寸低于100纳米且具有可控的表面结构。通过适当地改变介电层的顺序和厚度，可以调节这些核壳电极的光学和电学性质，包括表面等离子体频率。通过改变纳米柱的尺寸，纳米柱银的表面等离子体波长可从650纳米调谐至690纳米。向该结构中添加氧化铟锡层会使共振波长进一步向红外区域移动，并且根据结构中层的顺序和厚度，我们表明这种结构可应用于传感装置，包括增强硅作为光探测材料。
