【摘要】 设计了一种具有电磁感应透明效应(EIT)的光频段全介质超材料,其单元结构由垂直放置的倒L形介质块和水平放置的一字形介质块组成。根据米氏电磁谐振,两个介质块的作用分别相当于亮态四极子模和暗态偶极子模。基于米氏亮暗模之间的电磁耦合,在波长1 400nm附近模拟实现了透射峰值超过0.9的低损耗EIT效应。利用数值仿真和"二粒子"模型深入分析了低损耗EIT效应产生的物理机制。研究结果表明,透明窗的频谱位置与两个介质块的谐振频率失谐有关,透明窗的凹陷深度与亮模的损耗有关,透明窗的谐振强度和谐振宽度与两个介质块的耦合系数(距离)和暗模的损耗有关。提出的全介质超材料在慢光、非线性光学和光传感等方面具有潜在的应用价值。更多还原

【Abstract】 By combining a vertically inverted L-shaped dielectric block and a horizontally in-line dielectric rod into one unit structure,design an optical band all-dielectric metamaterial with an electromagnetic induced transparency(EIT)effect.According to the Mie electromagnetic resonance,the functions of the two dielectric blocks correspond to the bright quadrupole mode and the dark dipole mode,respectively.Based on the electromagnetic coupling between the Mie bright and dark modes,a low-loss EIT effect is obtained near the wavelength of 1 400 nm with a transmission peak exceeding 0.9.The numerical simulation and the "two-particle" model are used to deeply analyze the physical mechanism of low-loss EIT effect.The research results show that the spectral position of transparency window is related to the detuning of the resonant frequencies of the two dielectric blocks,the depth of the transmission window is related to the loss of the bright mode,the intensity and width of EIT resonance are related to the coupling coefficient(distance)of the two dielectric blocks and the loss of the dark mode.The proposed all-dielectric metamaterial has potential applications in slow light,nonlinear optics and optical sensing.更多还原