Surface plasmon polariton waveguides with subwavelength confinement<xref rid="cpb_27_9_094216fn1" ref-type="fn">*</xref><fn id="cpb_27_9_094216fn1"><label>*</label><p>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.</p></fn>

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 Zhipeng^{1, †}

(color online) (a) SEM image of a gold nanobelt. The sample was tilted by 45° to reveal the rectangular cross section. (b) High-resolution crystalline structure of the nanobelt. (c) Electron diffraction indicates the single-crystalline gold structure, reproduced from Ref. [91]. (d)–(e) Calculated field intensity of a 125 nm × 40 nm gold nanobelt for the m = 0 (d) and m = 1 (e) modes, reproduced from Ref. [92]. (f) SPP scattering peaks at different cross section aspect ratios in experiments (black) and simulations (white), reproduced from Ref. [93].