Open AccessMultifunctional metalens generation using bilayer all-dielectric metasurfaces
Author(s) -
Li Chen,
Yuan Hao,
Lin Zhao,
Ruihuan Wu,
Yue Liu,
Zhongchao Wei,
Ning Xu,
Zhaotang Li,
Hongzhan Liu
Publication year - 2021
Publication title -
optics express
Language(s) - Uncategorized
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.420003
Subject(s) - optics , materials science , polarization (electrochemistry) , ray , light intensity , bilayer , wavelength , optoelectronics , light field , reconfigurability , phase (matter) , physics , telecommunications , chemistry , biochemistry , quantum mechanics , membrane , computer science
Optical metasurfaces exhibit unprecedented ability in light field control due to their ability to locally change the phase, amplitude, and polarization of transmitted or reflected light. We propose a multifunctional metalens with dual working modes based on bilayer geometric phase elements consisting of low-loss phase change materials (Sb 2 Se 3 ) and amorphous silicon (a-Si). In transmission mode, by changing the crystalline state of the Sb 2 Se 3 scatterer, a bifocal metalens with an arbitrary intensity ratio at the telecommunication C-band is realized, and the total focusing efficiency of the bifocal metalens is as high as 78%. Also, at the resonance wavelength of the amorphous Sb 2 Se 3 scatterer, the scatterer can be regarded as a half-wave plate in reflection mode. The multifunctional metalens can reversely converge incident light into a focal point with a focusing efficiency of up to 30%. The high focusing efficiency, dynamic reconfigurability, and dual working modes of the multifunctional metalens contribute to polarization state detection, optical imaging, and optical data storage. In addition, the bilayer geometric phase elements can be easily extended to multilayer, which significantly improves the capability of manipulating the incident light field.