中国物理B ›› 2022, Vol. 31 ›› Issue (10): 107103-107103.doi: 10.1088/1674-1056/ac6ede
• CONDENSED MATTER: ELECTRONIC STRUCTURE, ELECTRICAL, MAGNETIC, AND OPTICAL PROPERTIES • 上一篇 下一篇
Chun-Lai Fu(付春来), Zhen-Long Zhao(赵振龙), Bo-Yu Ji(季博宇)†, Xiao-Wei Song(宋晓伟)‡, Peng Lang(郎鹏), and Jing-Quan Lin(林景全)
Chun-Lai Fu(付春来), Zhen-Long Zhao(赵振龙), Bo-Yu Ji(季博宇)†, Xiao-Wei Song(宋晓伟)‡, Peng Lang(郎鹏), and Jing-Quan Lin(林景全)
摘要: Clear imaging of surface plasmon polaritons (SPPs) is a prerequisite for SPPs-based applications. In this work, we demonstrate an improvement of near-field imaging of SPPs via directly comparing the visibility of the photoemission electron microscopy (PEEM) image of SPPs under one- and two-color laser excitation (also known as one- or two-color laser PEEM). By measuring the photoelectron yield and the contrast of the interference fringes of SPPs, we demonstrate that in addition to enhancing the photoemission yield, two-color laser PEEM can significantly improve the contrast between bright and dark fringes (nearly 4 times higher than that of one-color laser case). By recording the nonlinear order of the photoelectrons ejected from the bright and dark fringes, respectively, the underlying mechanism for the improved visibility is revealed. In addition, the influences of the polarization direction of 400-nm laser on the PEEM images of the SPPs with different wave vector directions are shown. These results can provide technical support for the development of SPPs-based communication devices and catalysis.
中图分类号: (Exchange, correlation, dielectric and magnetic response functions, plasmons)