基于类电磁诱导透明超材料的可调谐慢光器件

The tunable slow-light device based on electromagnetically induced transparency-like metamaterial

提出并设计了一款能够调控类电磁诱导透明现象的超材料,其单元结构由矩形开缝谐振环和加载变容二极管的开缝金属线组成。当调节变容二极管的电容值时,类电磁诱导透明现象中谐振峰频率会随着电容值的减少往低频方向移动,且对应的幅度值逐渐降低;当电容值降至0.79 pF时,类电磁诱导透明现象消失。通过表面电流分布、双谐振子模型和等效电路模型对其物理特性进行了分析。结合仿真和实验结果证明了该超材料可调谐功能的有效性。通过计算该超材料在不同电容值下的群时延表明其具有良好的慢光效应,因此在设计可调谐的慢光器件中具有潜在应用价值。

A tunable electromagnetically induced transparency-like metamaterial was proposed and designed, in which the unit cell was composed of a rectangle split-ring resonator and a cut wire-loaded variode. In the electromagnetically induced transparency-like(EIT-like) phenomenon, the frequency of the resonance peak moves to low frequency with decreasing capacitance, whereas the corresponding amplitude declines. When the capacitance decreases to 0.79 pF, the EIT-like phenomenon disappears. The surface current distributions, the two-oscillator model, and the equivalent circuit model were used to analyze the physical mechanism. Furthermore, the tunability of the proposed metamaterial was demonstrated by the simulated and measured results. The group delay with different capacitances shows perfect slow-light effect, which can be applied to design the tunable slow-light devices.