Thermally controllable Mie resonances in a water-based metamaterial

• Published in: Scientific reports Vol. 9; no. 1; p. 5417
• Main Authors: Sun, Xiaqing, Fu, Quanhong, Fan, Yuancheng, Wu, Hongjing, Qiu, Kepeng, Yang, Ruisheng, Cai, Weiqi, Zhang, Nan, Zhang, Fuli
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 01-04-2019; Nature Publishing Group
• Subjects: 639/624/399/1015; 639/624/400; 639/766/400/1103; Applied physics; Design; Experiments; Humanities and Social Sciences; multidisciplinary; Resonance; Science; Science (multidisciplinary); Water temperature
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-019-41681-5

Active control of metamaterial properties is of great significance for designing miniaturized and versatile devices in practical engineering applications. Taking advantage of the highly temperature-dependent permittivity of water, we demonstrate a water-based metamaterial comprising water cubes with thermally tunable Mie resonances. The dynamic tunability of the water-based metamaterial was investigated via numerical simulations and experiments. A water cube exhibits both magnetic and electric response in the frequency range of interest. The magnetic response is primarily magnetic dipole resonance, while the electric response is a superposition of electric dipole resonance and a smooth Fabry–Pérot background. Using temporal coupled-mode theory (TCMT), the role of direct scattering is evaluated and the Mie resonance modes are analyzed. As the temperature of water cube varies from 20 °C to 80 °C, the magnetic and electric resonance frequencies exhibit obvious blue shifts of 0.10 and 0.14 GHz, respectively.