Dynamic Hybrid Metasurfaces

• DOI: 10.1021/acs.nanolett.0c03625
• Publication Date: 2021-01-23T03:40:03Z
• Authors: Sajjad Abdollahra...; Omid Hemmatyar; Mohammad Taghinejad; Hossein Taghinejad; Yashar Kiarashinejad; Mohammadreza Zand...; Tianren Fan; Sanchit Deshmukh; Ali A. Eftekhar; Wenshan Cai; Eric Pop; Mostafa A. El-Sayed; Ali Adibi
• Keywords: next-generation reprogrammable meta.; Biophysics; incident light; FOS: Physical sciences; all-dielectric nanoantennas; Applied Physics (physics.app-ph); 02 engineering and technology; specular beam deflection; modulation depth; metasurface platform; Genetics; GST; phase-change material Ge 2 Sb 2 Te 5; Molecular Biology; Cancer; tunable metasurfaces; plasmonic-photonic resonances; reduced-dimension meta-atom; Cell Biology; Physics - Applied Physics; plasmonic-photonic metasurfaces; Dynamic Hybrid Metasurfaces Efficient; postfabrication tunable; metal-dielectric meta-atoms; 0210 nano-technology; Physical Sciences not elsewhere classified; Developmental Biology; Biological Sciences not elsewhere classified; Physics - Optics; Optics (physics.optics)

Efficient hybrid plasmonic-photonic metasurfaces that simultaneously take advantage of the potential of both pure metallic and all-dielectric nanoantennas are identified as an emerging technology in flat optics. Nevertheless, post-fabrication tunable hybrid metasurfaces are still elusive. Here, we present a reconfigurable hybrid metasurface platform by incorporating the phase-change material Ge$_{2}$Sb$_{2}$Te$_{5}$ (GST) into metal-dielectric meta-atoms for active and non-volatile tuning of properties of light. We systematically design a reduced-dimension meta-atom, which selectively controls the fundamental hybrid plasmonic-photonic resonances of the metasurface via the dynamic change of optical constants of GST without compromising the scattering efficiency. As a proof-of-concept, we experimentally demonstrate miniaturized tunable metasurfaces that control the amplitude and phase of incident light necessary for high-contrast optical switching and anomalous to specular beam deflection, respectively. Finally, we leverage a deep learning-based approach to present an intuitive low-dimensional visualization of the enhanced range of response reconfiguration enabled by the addition of GST. Our findings further substantiate dynamically tunable hybrid metasurfaces as promising candidates for the development of small-footprint energy harvesting, imaging, and optical signal processing devices.