Strong Circular Dichroism in Single Gyroid Optical Metamaterials
Strong Circular Dichroism in Single Gyroid Optical Metamaterials
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DOI：
10.1002/adom.201902131
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发表时间：
2020-05-07
影响因子：
9
通讯作者：
Wilts, Bodo D.
中科院分区：
文献类型：
--
作者：
Kilchoer, Cedric;Abdollahi, Narjes;Wilts, Bodo D.
在过去的二十年中，超材料已经导致越来越多的生物传感和纳米光子应用，由于仔细控制光传播通过亚波长特征的可能性。手性纳米结构（其特征在于没有任何镜像对称性），特别是，产生独特的手性光学性质，如圆二色性和光学活性。在这里，提出了一种具有65 nm的周期性的回转光学超材料，其在可见波长处表现出强圆二色性。这种自下而上的方法，基于金属复制的螺旋状形态的三块薄膜，产生了大面积的周期性光学超材料。观察到金和银螺旋状异向材料在可见光波段具有很强的圆二色性。结果表明，圆二色性是内在的螺旋状纳米结构的旋向性和它的tunneling证明。的光学效应进行了讨论，并与其他现有的系统相比，显示了大规模的圆形过滤器和手性传感的自下而上的方法的潜力。
Over the past two decades, metamaterials have led to an increasing number of biosensing and nanophotonic applications due to the possibility of a careful control of light propagating through subwavelength features. Chiral nanostructures (characterized by the absence of any mirror symmetry), in particular, give rise to unique chiro-optical properties such as circular dichroism and optical activity. Here, a gyroid optical metamaterial with a periodicity of 65 nm exhibiting a strong circular dichroism at visible wavelengths is presented. This bottom-up approach, based on metallic replication of the gyroid morphology in triblock terpolymer films, generates a large area of periodic optical metamaterials. A strong circular dichroism in gold and silver gyroid metamaterials at visible wavelengths is observed. It is shown that the circular dichroism is inherently linked to the handedness of the gyroid nanostructure and its tuneability is demonstrated. The optical effects are discussed and compared to other existing systems, showing the potential of bottom-up approaches for large-scale circular filters and chiral sensing.