Polarization-driven thermal emission regulator based on self-aligned GST nanocolumns

Joo Hwan Ko; Do Hyeon Kim; Sung-Hoon Hong; Sun-Kyung Kim; Young Min Song

doi:10.1016/j.isci.2022.105780

Polarization-driven thermal emission regulator based on self-aligned GST nanocolumns

iScience. 2022 Dec 9;26(1):105780. doi: 10.1016/j.isci.2022.105780. eCollection 2023 Jan 20.

Authors

Joo Hwan Ko¹, Do Hyeon Kim¹, Sung-Hoon Hong², Sun-Kyung Kim³, Young Min Song^{1

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Affiliations

¹ School of Electrical Engineering and Computer Science, Gwangju Institute of Science and Technology, Gwangju 61005, Republic of Korea.
² ICT Materials and Components Research Laboratory, Electronics and Telecommunications Research Institute (ETRI), Daejeon 34129, Republic of Korea.
³ Department of Applied Physics, Kyung Hee University, Gyeonggi-do, Yongin-si 17104, Republic of Korea.
⁴ Anti-Viral Research Center, Gwangju Institute of Science and Technology, Gwangju 61005, Republic of Korea.
⁵ AI Graduate School, Gwangju Institute of Science and Technology, Gwangju 61005, Republic of Korea.

Abstract

The increasing advances in thermal radiation regulators have attracted growing interest, particularly in infrared sources, thermal management, and camouflage. Despite many advances in dynamic thermal emitters with great controllability, sustained external energy is required to maintain the desired emission. In this study, we present a polarization-driven thermal emission regulator based on a two-way control: i) phase change and ii) polarization tuning. Based on a conventional, non-volatile phase change material, i.e., Ge₂Sb₂Te₅ (GST), we newly introduce an anisotropic medium for facile emissivity regulation without heat energy consumption. A rigorous coupled-wave analysis method provides design guidelines for finding optimal structural parameters. We utilized a simple glancing angle deposition process which induces tilted self-aligned nanocolumns with anisotropic properties. The fabricated sample shows polarization-sensitive thermal regulation through thermal imaging spectroscopic measurement. Additionally, we manufactured a multispectral visibly/thermally camouflaged patch that identifies encrypted information at a specific polarization state for a proof-of-concept demonstration.

Keywords: Nanotechnology; Thermal engineering; Thermal property.