Interdisciplinary Materials Science Program, Vanderbilt University, Nashville, Tennessee 37212, USA.
Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA.
Nat Commun. 2014 Dec 16;5:5753. doi: 10.1038/ncomms6753.
Metasurface analogues of electromagnetically induced transparency (EIT) have been a focus of the nanophotonics field in recent years, due to their ability to produce high-quality factor (Q-factor) resonances. Such resonances are expected to be useful for applications such as low-loss slow-light devices and highly sensitive optical sensors. However, ohmic losses limit the achievable Q-factors in conventional plasmonic EIT metasurfaces to values <~10, significantly hampering device performance. Here we experimentally demonstrate a classical analogue of EIT using all-dielectric silicon-based metasurfaces. Due to extremely low absorption loss and coherent interaction of neighbouring meta-atoms, a Q-factor of 483 is observed, leading to a refractive index sensor with a figure-of-merit of 103. Furthermore, we show that the dielectric metasurfaces can be engineered to confine the optical field in either the silicon resonator or the environment, allowing one to tailor light-matter interaction at the nanoscale.
近年来，基于电磁感应透明（EIT）的亚表面模拟成为了纳米光子学领域的研究热点，因为它们能够产生高品质因子（Q 因子）共振。这种共振有望应用于低损耗慢光器件和高灵敏度光学传感器等领域。然而，欧姆损耗限制了传统等离子体 EIT 亚表面所能达到的 Q 因子值<~10，这显著影响了器件性能。本文利用全介质硅基亚表面实验演示了一种经典的 EIT 模拟。由于极低的吸收损耗和相邻亚原子的相干相互作用，观察到的 Q 因子为 483，从而实现了品质因数为 103 的折射率传感器。此外，本文还表明，可以对介电亚表面进行设计，以在硅谐振器或环境中限制光场，从而可以在纳米尺度上调整光物质相互作用。
