title: Single-Band 2-nm-Line-Width Plasmon Resonance in a Strongly Coupled Au Nanorod.
abstract: This paper reports a dramatic reduction in plasmon resonance line width of a single Au nanorod by coupling it to a whispering gallery cavity of a silica microfiber. With fiber diameter below 6 μm, strong coupling between the nanorod and the cavity occurs, leading to evident mode splitting and spectral narrowing. Using a 1.46-μm-diameter microfiber, we obtained single-band 2-nm-line-width plasmon resonance in an Au nanorod around a 655-nm-wavelength, with a quality factor up to 330 and extinction ratio of 30 dB. Compared to an uncoupled Au nanorod, the strongly coupled nanorod offers a 30-fold enhancement in the peak intensity of plasmonic resonant scattering.
authors.affiliation: State Key Laboratory of Modern Optical Instrumentation, College of Optical Science and Engineering, Zhejiang University , Hangzhou 310027, China.|Department of Physics, King's College London , Strand, London WC2R 2LS, United Kingdom.
authors.forename: Pan
authors.initials: P
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Modern Optical Instrumentation, College of Optical Science and Engineering, Zhejiang University , Hangzhou 310027, China.
authors.forename: Yipei
authors.initials: Y
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Modern Optical Instrumentation, College of Optical Science and Engineering, Zhejiang University , Hangzhou 310027, China.
authors.forename: Zongyin
authors.initials: Z
authors.lastname: Yang
authors.affiliation: State Key Laboratory of Modern Optical Instrumentation, College of Optical Science and Engineering, Zhejiang University , Hangzhou 310027, China.
authors.forename: Xin
authors.initials: X
authors.lastname: Guo
authors.affiliation: State Key Laboratory of Modern Optical Instrumentation, College of Optical Science and Engineering, Zhejiang University , Hangzhou 310027, China.
authors.forename: Xing
authors.initials: X
authors.lastname: Lin
authors.affiliation: State Key Laboratory for Mesoscopic Physics, Department of Physics, Peking University , Beijing 100871, China.
authors.forename: Xiao-Chong
authors.initials: XC
authors.lastname: Yu
authors.affiliation: State Key Laboratory for Mesoscopic Physics, Department of Physics, Peking University , Beijing 100871, China.
authors.forename: Yun-Feng
authors.initials: YF
authors.lastname: Xiao
authors.affiliation: State Key Laboratory of Modern Optical Instrumentation, College of Optical Science and Engineering, Zhejiang University , Hangzhou 310027, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Fang
authors.affiliation: State Key Laboratory of Modern Optical Instrumentation, College of Optical Science and Engineering, Zhejiang University , Hangzhou 310027, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Zhang
authors.affiliation: State Key Laboratory for Mesoscopic Physics, Department of Physics, Peking University , Beijing 100871, China.
authors.forename: Guowei
authors.initials: G
authors.lastname: Lu
authors.affiliation: State Key Laboratory for Mesoscopic Physics, Department of Physics, Peking University , Beijing 100871, China.
authors.forename: Qihuang
authors.initials: Q
authors.lastname: Gong
authors.affiliation: State Key Laboratory of Modern Optical Instrumentation, College of Optical Science and Engineering, Zhejiang University , Hangzhou 310027, China.
authors.forename: Limin
authors.initials: L
authors.lastname: Tong
keywords: Au nanorods; Localized surface plasmon resonance; line width; microfibers; strong coupling; whispering gallery modes