Design and analysis of electrothermal metasurfaces

• Published in: Frontiers in Energy Vol. 17; no. 1; pp. 134 - 140
• Main Authors: LIU, Xiu, LI, Zhuo, WANG, Zexiao, YUN, Hyeong Seok, SHEN, Sheng
• Format: Journal Article
• Language: English
• Published: Beijing Higher Education Press 2023; Springer Nature B.V
• Subjects: Arrays; Aspect ratio; Design factors; Energy; Energy Systems; finite size; I.R. radiation; Infrared radiation; metasurface; Metasurfaces; modulated thermal infrared radiation; Nanorods; nanosecond response time; Research Article; Resonance; Response time; Size effects; sub-Kelvin temperature uniformity; aspect ratio; sub-Kelvin temperature uniformity; finite size; nanosecond response time; modulated thermal infrared radiation; metasurface
• ISSN: 2095-1701; 2095-1698
• DOI: 10.1007/s11708-022-0841-9

Electrothermal metasurfaces have garnered considerable attention owing to their ability to dynamically control thermal infrared radiation. Although previous studies were mainly focused on metasurfaces with infinite unit cells, in practice, the finite-size effect can be a critical design factor for developing thermal metasurfaces with fast response and broad temperature uniformity. Here, we study the thermal metasurfaces consisting of gold nanorods with a finite array size, which can achieve a resonance close to that of the infinite case with only several periods. More importantly, such a small footprint due to the finite array size yields response time down to a nanosecond level. Furthermore, the number of the unit cells in the direction perpendicular to the axis of nanorods is found to be insensitive to the resonance and response time; thus, providing a tunable aspect ratio that can boost the temperature uniformity in the sub-Kelvin level.