Zhang Ping, Dong Yin, Li Xubo, Cao Xinxin, Yang Youfeng, Yu Guohao, Yang Shengpeng, Wang Shaomeng, Gong Yubin
School of Electronic Science and Engineering, University of Electronic Science and Technology of China, Chengdu 610054, China.
Suzhou Institute of Nano-Tech and Nano-Bionics (SINANO), CAS, Suzhou 215123, China.
Micromachines (Basel). 2024 May 30;15(6):723. doi: 10.3390/mi15060723.
Surface plasmon polaritons (SPPs) have become a research hotspot due to their high intensity and subwavelength localization. Through free-electron excitation, a portion of the momentum of moving electrons can be converted into SPPs. Converting highly localized SPPs into a radiated field is an approach with the potential to aid in the development of a light radiation source. Reducing losses of SPPs is currently a critical challenge that needs to be addressed. The lifetime of SPPs in metal films is longer than that in metal blocks. Traditional optical gratings can transform SPPs into radiation to avoid the decay of SPPs in metal; however, they are created by etching metal films, so they tend to alter the dispersion characteristics of these films and will emit radiation in the direction perpendicular to the metal surface. This paper proposes an approach to converting the SPPs of a metal film excited by free electrons into a radiation field via lateral grating and obtaining in-plane radiation. We investigate the properties of SPP lateral radiation. The study of lateral radiation from metal films holds significant importance for SPP radiation sources and SPP on-chip circuit development.
表面等离激元极化激元（SPPs）因其高强度和亚波长局域性而成为研究热点。通过自由电子激发，移动电子的一部分动量可以转化为表面等离激元极化激元。将高度局域的表面等离激元极化激元转换为辐射场是一种有助于光辐射源发展的潜在方法。降低表面等离激元极化激元的损耗是目前需要解决的关键挑战。表面等离激元极化激元在金属薄膜中的寿命比在金属块中的寿命长。传统的光学光栅可以将表面等离激元极化激元转换为辐射，以避免表面等离激元极化激元在金属中衰减；然而，它们是通过蚀刻金属薄膜形成的，因此往往会改变这些薄膜的色散特性，并会在垂直于金属表面的方向上发射辐射。本文提出了一种通过横向光栅将自由电子激发的金属薄膜的表面等离激元极化激元转换为辐射场并获得面内辐射的方法。我们研究了表面等离激元极化激元横向辐射的特性。金属薄膜横向辐射的研究对于表面等离激元极化激元辐射源和片上表面等离激元极化激元电路的发展具有重要意义。
