Li, HongliangLee, Woo BinZhou, ChangyiChoi, Duk YongLee, Sang Shin2025-06-242025-06-24ORCID:/0000-0002-5339-3085/work/163474818http://www.scopus.com/inward/record.url?scp=85119598888&partnerID=8YFLogxKhttps://hdl.handle.net/1885/733764634A flat retroreflector based on metasurface doublet is proposed and created via lithographical nanofabrication. A high-speed wireless optical communication system with wide-angle tolerance is demonstrated at a telecommunications wavelength of ? = 1550 nm.This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Ministry of Education (Grant No. 2018R1A6A1A03025242) and the Korean government (MSIT) (No. 2020R1A2C3007007) and has been conducted by a research grant of Kwangwoon University in 2021. The work was partly performed at the ACT node of the Australian National Fabrication Facility.enPublisher Copyright: © OSA 2021, © 2021 The Author(s)202185119598888