Center for Terahertz waves and College of Precision Instrument and Optoelectronics Engineering, Tianjin University and the Key Laboratory of Optoelectronics Information and Technology (Ministry of Education), Tianjin 300072, China.
Cooperative Innovation Center of Terahertz Science, Chengdu 610054, China.
Sci Rep. 2016 Nov 29;6:37861. doi: 10.1038/srep37861.
As an essential functionality, flexible focusing of surface plasmons (SPs) is of particular interest in nonlinear optics and highly integrated plasmonic circuitry. Here, we developed a versatile plasmonic metalens, a metasurface comprised of coupled subwavelength resonators, whose optical responses exhibit a remarkable feature of electromagnetically induced transparency (EIT). We demonstrate numerically and experimentally how a proper spatial design of the unit elements steers SPs to arbitrary foci based on the holographic principles. More specifically, we show how to control the interaction between the constituent EIT resonators to efficiently manipulate the focusing intensity of SPs. We also demonstrated that the proposed metalens is capable of achieving frequency division multiplexing. The power and simplicity of the proposed design would offer promising opportunities for practical plasmonic devices.
作为一项基本功能，表面等离激元（SPs）的灵活聚焦在非线性光学和高度集成的等离子体电路中尤为重要。在这里，我们开发了一种多功能的等离子体超透镜，这是一种由耦合亚波长谐振器组成的超表面，其光学响应表现出显著的电磁感应透明（EIT）特性。我们通过数值和实验演示了如何根据全息原理通过单元元件的适当空间设计将 SPs 引导至任意焦点。更具体地说，我们展示了如何控制组成 EIT 谐振器之间的相互作用，以有效地操纵 SPs 的聚焦强度。我们还表明，所提出的超透镜能够实现频分复用。所提出设计的功率和简单性将为实用的等离子体器件提供有前途的机会。
