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Visible light focusing flat lenses based on hybrid dielectric-metal metasurface reflector-arrays.

ABSTRACT: Conventional metasurface reflector-arrays based on metallic resonant nanoantenna to control the wavefront of light for focusing always suffer from strong ohmic loss at optical frequencies. Here, we overcome this challenge by constructing a non-resonant, hybrid dielectric-metal configuration consisting of TiO₂ nanofins associated with an Ag reflector substrate that provides a broadband response and high polarization conversion efficiency in the visible range. A reflective flat lens based on this configuration shows an excellent focusing performance with the spot size close to the diffraction limit. Furthermore, by employing the superimposed phase distribution design to manipulate the wavefront of the reflected light, various functionalities, such as multifocal and achromatic focusing, are demonstrated for the flat lenses. Such a reflective flat lens will find various applications in visible light imaging and sensing systems.

SUBMITTER: Fan Q

PROVIDER: S-EPMC5362929 | biostudies-literature | 2017 Mar

REPOSITORIES: biostudies-literature

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Visible light focusing flat lenses based on hybrid dielectric-metal metasurface reflector-arrays.

Fan Qingbin Q Huo Pengcheng P Wang Daopeng D Liang Yuzhang Y Yan Feng F Xu Ting T

Scientific reports 20170323

Conventional metasurface reflector-arrays based on metallic resonant nanoantenna to control the wavefront of light for focusing always suffer from strong ohmic loss at optical frequencies. Here, we overcome this challenge by constructing a non-resonant, hybrid dielectric-metal configuration consisting of TiO<sub>2</sub> nanofins associated with an Ag reflector substrate that provides a broadband response and high polarization conversion efficiency in the visible range. A reflective flat lens bas ...[more]

PMID: 28332611

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