Surface plasmon polariton waveguides with subwavelength confinement*

Project supported by the National Natural Science Foundation of China (Grant Nos. 11704266 and 11774245), the Fok Ying Tung Education Foundation, China (Grant No. 151010), the Scientific Research Base Development Program of Beijing Municipal Commission of Education, China, the General Foundation of Beijing Municipal Commission of Education, China (Grant No. KM201810028006), and the Training Program of the Major Research Plan of Capital Normal University, China.
Yang Longkun1, Li Pan1, Wang Hancong2, Li Zhipeng1, †
       

(color online) (a) Coupled metal nanowire and mirror system. The change in thickness of the separating layer can be precisely detected. (b) High-resolution TEM image of the cross section of the nanowire and mirror system. The scale bar is 30 nm. (c) Calculated scattering spectrum of a 45-nm-diameter Au nanowire on a gold film with 2 nm separation. (d) Measured resonant peak of the cavity plasmon mode as a function of the Al2O3 layer thickness, reproduced from Ref. [103]. (e) Remote excitation SERS of a live HeLa cell by Ag nanowire. (f) SEM image of a typical tungsten tip with Ag nanowires attached. (g) Magnified image of the probe tip, reproduced from Ref. [104]. (h) Schematic of the experimental setup, showing the integration of the nanofocusing remote SERS sensor into an AFM microscopy, reproduced from Ref. [105].