论文标题
飞秒脉冲散射光谱揭示的2D材料辅助的缝隙等离子
2D-Material-Assisted Bistable Switching of Gap Plasmons Disclosed By Femtosecond Pulse Scattering Spectra
论文作者
论文摘要
用飞秒激光泵送摩擦式等离子天线的纳米等离子天线。随着激光功率变化，散射线宽和峰强度趋势的突然转弯被实验观察到。动态等离子体演变的理论建模属性属性在两个等离子状态之间转向过渡，其四波混合效率的通用切换阈值约为0.14％。从非线性间隙电流到间隙等离子体的强烈反馈以及四个和高阶波混合的参与来实现这种双重性。这项工作揭示了制造节能非线性等离子元件的途径。
Nanosphere-on-mirror plasmonic antennas, each having a monolayer graphene or MoS2 sheet in the gap, were pumped with a femtosecond laser. Abrupt turnings in the scattering linewidth and peak intensity trends as the laser power changed were experimentally observed. Theoretical modelling of dynamic plasmon evolvement attributes the turning to transitioning between two plasmon states, with a universal switching threshold of four-wave mixing efficiency around 0.14%. This bistability is rendered by a strong feedback from the nonlinear gap current to the gap plasmons, and involvement of both four and high-order wave mixing. This work reveals a pathway to making energy efficient nonlinear plasmonic elements.
