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Title: Thermally Tunable Far-Infrared Metasurfaces Enabled by Ge2Sb2Te5 Phase-Change Material
The development of active metadevices continues to present keystone challenges in fields of plasmonics and photonics. Here, we demonstrate an analogue of electromagnetically induced transparency (EIT) effect in a far-infrared metasurface device via near-field coupling of bright and quasi-dark resonances resonating at nearly the same frequency with contrasting line widths. The proposed metasurface was further optimized numerically in order to demonstrate a reconfiguration effect (frequency-shift of the spectral response). The tunability property of the device is achieved by incorporating a thin layer of Ge 2 Sb 2 Te 5 (GST), a temperature-driven phase change material (PCM). Theoretical analysis based on a coupled Lorentz oscillator model explains the physical mechanism in the proposed design and shows a good agreement with the observed results. Such active hybrid EIT metadevices could have applications in tunable slow-light effects, delay bandwidth management and ultrafast laser induced switching.  more » « less
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IEEE Rapid
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National Science Foundation
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