Controllable Polarization‐Insensitive and Large‐Angle Beam Switching with Phase‐Change Metasurfaces. Issue 5 (8th January 2022)

• Record Type: Journal Article
• Authors: Nemati, Arash; Yuan, Guanghui; Deng, Jie; Huang, Aihong; Wang, Weide; Toh, Yeow Teck; Teng, Jinghua; Wang, Qian
• Is Part Of: Advanced optical materials. Volume 10:Issue 5(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-01-08
• Subjects: controllable beam switching -- large‐angle beam switching -- phase‐change metasurfaces -- polarization insensitive; Optical materials -- Periodicals; Photonics -- Periodicals; 620.11295
• DOI: 10.1002/adom.202101847
• Languages: English
• ISSNs: 2195-1071

Abstract

Abstract: The development of high‐efficiency compact non‐mechanical beam tuning devices has attracted a lot of attention for light detection and ranging, augmented reality display, and chip‐to‐chip communication. Owing to the fast wavefront manipulation in an ultra‐thin dimension, metasurfaces have been regarded as potential substitutes for traditional tunable optical components toward further miniaturization and low power consumption. However, most beam tuning metasurfaces currently are polarization‐sensitive and designed to work in reflection mode, which limit their applications in integrated optical systems for full‐range steering. In this paper, a transmission mode polarization‐insensitive beam switching metasurface based on nonvolatile phase‐change material Ge2 Sb2 Te5 is proposed and experimentally demonstrated at the telecommunication wavelength. The high transmission efficiency with a large switching angle of up to 75° is achievable for potentially full‐range beam steering applications. As a proof of concept, the transmitted beam with a switching angle of 15° and directivity of 82.4% is demonstrated. In addition, by controlling the phase transition in the intermediate states, the metasurface can be used as a tunable beam splitter to control the ratio of the beam power between two predesigned transmission angles. The demonstrated phase‐change metasurfaces pave the way for achieving high‐efficiency dynamic beam steering for various important applications. Abstract : A transmission mode polarization‐insensitive beam switching metasurface based on nonvolatile phase‐change material Ge2 Sb2 Te5 is proposed at the telecommunication wavelength. The transmitted laser beam with a switching angle of 15° and directivity of 82.4% is experimentally demonstrated. In addition, a large switching angle of up to 75° with high efficiency is achievable for potentially full‐range beam steering applications.