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arXiv · 1804.08339

An Ultra-high Numerical Aperture Metalens at Visible Wavelengths

Haowen Liang·Qiaoling Lin·Xiangsheng Xie·Qian Sun·Yin Wang·Lidan Zhou·Lin Liu·Xiangyang Yu·Jianying Zhou·Thomas F Krauss·Juntao Li
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Abstract

We demonstrate a metalens with NA = 0.98 in air, a bandwidth (FWHM) of 274 nm and a focusing efficiency of 67% at 532 nm wavelength, which is close to the transmission performance of a TiO2 metalens. Moreover, and uniquely so, our metalens can be front-immersed into immersion oil and achieve an ultra-high NA of 1.48 experimentally and 1.73 theoretically, thereby demonstrating the highest NA of any metalens in the visible regime reported to the best of our knowledge.

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Haowen Liang, Qiaoling Lin, Xiangsheng Xie, Qian Sun, Yin Wang, Lidan Zhou, Lin Liu, Xiangyang Yu, Jianying Zhou, Thomas F Krauss, Juntao Li. 2018-04-23. An Ultra-high Numerical Aperture Metalens at Visible Wavelengths. https://doi.org/10.1021/acs.nanolett.8b01570

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