Open AccessNear-infrared thermally modulated varifocal metalens based on the phase change material Sb2S3
Author(s) -
Shuai Qin,
Ning Xu,
Hui Huang,
Kaiqian Jie,
Hongzhan Liu,
Jianping Guo,
Hongyun Meng,
Faqiang Wang,
Xiangbo Yang,
Zhongchao Wei
Publication year - 2021
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.420014
Subject(s) - optics , materials science , refractive index , amorphous solid , focal point , diffraction , phase change , phase (matter) , infrared , focal length , optoelectronics , diffraction efficiency , cardinal point , physics , lens (geology) , chemistry , organic chemistry , engineering physics , quantum mechanics
Focus-tunable metalenses play an indispensable role in the development of integrated optical systems. In this paper, the phase change material Sb 2 S 3 is used in a thermally modulated varifocal metalens based on PB-phase for the first time. Sb 2 S 3 not only has a real part of refractive index shift between the amorphous and crystalline state but also has low losses in both amorphous and crystalline states in the near-infrared region. By switching Sb 2 S 3 between the two states, a metalens doublet with a variable focal length is proposed. Moreover, the full width at half maximum of each focal point is close to the diffraction limit. And the focusing efficiency can be over 50% for the two focal points. Together with the advantage of precise thermal control, the proposed metalens has great potential in the application of multi-functional devices, biomedical science, communication and imaging.