Chinese Optics Letters, 2021, 19 (1): 013601, Published Online: Dec. 18, 2020
Chiral plasmonic nanostructure of twistedly stacked nanogaps Download: 766次
metal-insulator-metal structure nanogaps gap mode twisted stacking charge distribution chiral response
Abstract
Nanogap plasmonic structures with strong coupling between separated components have different responses to orthogonal-polarized light, giving rise to giant optical chirality. Here, we proposed a three-dimensional (3D) nanostructure that consists of two vertically and twistedly aligned nanogaps, showing the hybridized charge distribution within 3D structures. It is discovered that the structure twisted by 60° exhibits plasmonic coupling behavior with/without gap modes for different circular-polarized plane waves, showing giant chiral response of 60% at the wavelength of 1550 nm. By controlling the disk radius and the insulator layer, the circular dichroism signal can be further tuned between 1538 and 1626 nm.
Jian Zhang, Rui Tu, Chao Huang, Xiaoli Yao, Xin Hu, Haixiong Ge, Xuefeng Zhang. Chiral plasmonic nanostructure of twistedly stacked nanogaps[J]. Chinese Optics Letters, 2021, 19(1): 013601.