Liaoning Key Laboratory of Marine Sensing and Intelligent Detection, Dalian Maritime University, 116026 Dalian, China.
Information Science and Technology College, Dalian Maritime University, 116026 Dalian, China.
J Phys Chem Lett. 2023 Feb 16;14(6):1403-1410. doi: 10.1021/acs.jpclett.2c03659. Epub 2023 Feb 2.
This paper describes a quasi-planar chiral metamaterial of metal-insulator-metal (MIM) tetramer arrays that support multiplasmon modes from a hybridization scheme to achieve significant chiroptical responses with the largest circular dichroism (CD) value of 42%. The chiroptical responses can be actively switched on and off by tuning the field coupling regime from near field to far field through the insulator (or spacer) thickness. Numerical calculations demonstrate that near-field coupling of the hybridized plasmons on the stacked metallic tetramers governs the chiroptical responses at small insulator thickness ( < 160 nm). In contrast, far-field coupling of the plasmon radiations dominates at large spacing ( > 160 nm) as phase retardation plays a crucial role. The quasi-planar chiral metamaterial with tunable plasmonic chirality enables efficient light modulation for polarization conversion: from circular to elliptical/linear polarization.
本文描述了一种基于金属-绝缘体-金属（MIM）四元阵列的拟近平坦手性超材料，它通过杂化方案支持多等离子体模式，实现了具有最大圆二色性（CD）值为 42%的显著手性响应。通过调节绝缘体（或间隔物）厚度，在手性超材料中可以从近场到远场的转变来实现手性响应的主动开启和关闭。数值计算表明，堆叠金属四元体上的杂化等离子体的近场耦合控制了小绝缘体厚度（<160nm）下的手性响应。相比之下，在较大间隔（>160nm）下，等离子体辐射的远场耦合占主导地位，因为相位延迟起着至关重要的作用。这种具有可调等离子体手性的拟近平坦手性超材料能够实现高效的光调制，用于偏振转换：从圆偏振到椭圆/线偏振。
