School of Electronic and Electrical Engineering, Wuhan Textile University, Wuhan, Hubei, 430073, People's Republic of China.
Department of Electrical Engineering, The Pennsylvania State University, University Park, PA, 16802, USA.
Sci Rep. 2017 Jun 28;7(1):4326. doi: 10.1038/s41598-017-04692-8.
Hybrid metamaterials that exhibit reconfigurable responses under external stimulus, such as electric fields and light radiation, have only recently been demonstrated by combining active media with patterned metallic structures. Nevertheless, hybrid terahertz (THz) metamaterials whose spectral performance can be dynamically tuned over a large scale remain rare. Compared with most active media (for instance, silicon) that provide limited activity, vanadium dioxide (VO), which exhibits an insulator-to-metal transition, has been recently explored to facilitate dynamically tunable metamaterials. More importantly, the phase transition yields a three orders of magnitude increase in THz electrical conductivity, which suggests the potential for creating VO based hybrid resonators that operate at THz frequencies. Here, we show that an integration of VO structures and conventional metallic resonating components can enable a class of highly tunable THz metamaterials. Considering the widely studied phase-transition dynamics in VO, the proposed hybrid metamaterials are capable of offering ultrafast modulation of THz radiation.
混合超材料在外部刺激下表现出可重构的响应，例如电场和光辐射，最近通过将有源介质与图案化金属结构相结合才得以实现。然而，能够在很大范围内动态调谐光谱性能的混合太赫兹 (THz) 超材料仍然很少见。与大多数提供有限活性的有源介质（例如硅）相比，具有绝缘到金属转变的氧化钒 (VO) 最近被探索用于促进动态可调谐超材料。更重要的是，相变导致 THz 电导率增加三个数量级，这表明有可能创建基于 VO 的混合谐振器，这些谐振器可在 THz 频率下工作。在这里，我们表明 VO 结构和传统金属谐振元件的集成可以实现一类高度可调谐的 THz 超材料。考虑到 VO 中广泛研究的相变动力学，所提出的混合超材料能够提供 THz 辐射的超快调制。
