Electrically Reconfigurable Phase‐Change Transmissive Metasurface

• Published in: Advanced materials (Weinheim) Vol. 36; no. 36; pp. e2400627 - n/a
• Main Authors: Popescu, Cosmin Constantin, Aryana, Kiumars, Garud, Parth, Dao, Khoi Phuong, Vitale, Steven, Liberman, Vladimir, Bae, Hyung‐Bin, Lee, Tae‐Woo, Kang, Myungkoo, Richardson, Kathleen A., Julian, Matthew, Ocampo, Carlos A. Ríos, Zhang, Yifei, Gu, Tian, Hu, Juejun, Kim, Hyun Jung
• Format: Journal Article
• Language: English
• Published: Germany Wiley Subscription Services, Inc 01-09-2024
• Subjects: Beam steering; Cycle ratio; Data storage; Gas sensors; Medical imaging; Memory devices; metasurfaces; Optical components; Optical properties; Optics; Optoelectronic devices; Phase change materials; photonic devices; reconfigurable optics; Reconfiguration; phase change materials; metasurfaces; reconfigurable optics; photonic devices
• ISSN: 0935-9648; 1521-4095; 1521-4095
• DOI: 10.1002/adma.202400627

Programmable and reconfigurable optics hold significant potential for transforming a broad spectrum of applications, spanning space explorations to biomedical imaging, gas sensing, and optical cloaking. The ability to adjust the optical properties of components like filters, lenses, and beam steering devices could result in dramatic reductions in size, weight, and power consumption in future optoelectronic devices. Among the potential candidates for reconfigurable optics, chalcogenide‐based phase change materials (PCMs) offer great promise due to their non‐volatile and analogue switching characteristics. Although PCM have found widespread use in electronic data storage, these memory devices are deeply sub‐micron‐sized. To incorporate phase change materials into free‐space optical components, it is essential to scale them up to beyond several hundreds of microns while maintaining reliable switching characteristics. This study demonstrated a non‐mechanical, non‐volatile transmissive filter based on low‐loss PCMs with a 200 × 200 µm2 switching area. The device/metafilter can be consistently switched between low‐ and high‐transmission states using electrical pulses with a switching contrast ratio of 5.5 dB. The device was reversibly switched for 1250 cycles before accelerated degradation took place. The work represents an important step toward realizing free‐space reconfigurable optics based on PCMs.
Active metasurfaces are emerging as a new avenue for creating compact, high‐performance reconfigurable optical devices. This study demonstrates a non‐volatile transmissive metafilter based on low‐loss PCMs deposited on a 200 × 200 µm2 microheater. The metafilter can be electrically switched between low‐ and high‐transmission states using no mechanical movements with a switching contrast ratio of 5.5 dB.