title: Fluorescent Nanowire Ring Illumination for Wide-Field Far-Field Subdiffraction Imaging.
abstract: Here we demonstrate an active method which pioneers in utilizing a combination of a spatial frequency shift and a Stokes frequency shift to enable wide-field far-field subdiffraction imaging. A fluorescent nanowire ring acts as a localized source and is combined with a film waveguide to produce omnidirectional illuminating evanescent waves. Benefitting from the high wave vector of illumination, the high spatial frequencies of an object can be shifted to the passband of a conventional imaging system, contributing subwavelength spatial information to the far-field image. A structure featuring 70-nm-wide slots spaced 70 nm apart has been resolved at a wavelength of 520 nm with a 0.85 numerical aperture standard objective based on this method. The versatility of this approach has been demonstrated by imaging integrated chips, Blu-ray DVDs, biological cells, and various subwavelength 2D patterns, with a viewing area of up to 1000  μm^{2}, which is one order of magnitude larger than the previous far-field and full-field nanoscopy methods. This new resolving technique is label-free, is conveniently integrated with conventional microscopes, and can potentially become an important tool in cellular biology, the on-chip industry, as well as other fields requiring wide-field nanoscale visualization.
authors.affiliation: State Key Laboratory of Modern Optical Instrumentation, College of Optical Science and Engineering, Zhejiang University, Hangzhou 310027, China.
authors.forename: Xiaowei
authors.initials: X
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Modern Optical Instrumentation, College of Optical Science and Engineering, Zhejiang University, Hangzhou 310027, China.
authors.forename: Cuifang
authors.initials: C
authors.lastname: Kuang
authors.affiliation: State Key Laboratory of Modern Optical Instrumentation, College of Optical Science and Engineering, Zhejiang University, Hangzhou 310027, China.
authors.forename: Xiang
authors.initials: X
authors.lastname: Hao
authors.affiliation: State Key Laboratory of Modern Optical Instrumentation, College of Optical Science and Engineering, Zhejiang University, Hangzhou 310027, China.
authors.forename: Chenlei
authors.initials: C
authors.lastname: Pang
authors.affiliation: State Key Laboratory of Modern Optical Instrumentation, College of Optical Science and Engineering, Zhejiang University, Hangzhou 310027, China.
authors.forename: Pengfei
authors.initials: P
authors.lastname: Xu
authors.affiliation: State Key Laboratory of Modern Optical Instrumentation, College of Optical Science and Engineering, Zhejiang University, Hangzhou 310027, China.
authors.forename: Haifeng
authors.initials: H
authors.lastname: Li
authors.affiliation: School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0245, USA.
authors.forename: Ying
authors.initials: Y
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Modern Optical Instrumentation, College of Optical Science and Engineering, Zhejiang University, Hangzhou 310027, China.
authors.forename: Chao
authors.initials: C
authors.lastname: Yu
authors.affiliation: Key Laboratory for Biomedical Engineering of the Ministry of Education, Department of Biomedical Engineering, Zhejiang University, Hangzhou 310027, China.
authors.forename: Yingke
authors.initials: Y
authors.lastname: Xu
authors.affiliation: Key Laboratory for Biomedical Engineering of the Ministry of Education, Department of Biomedical Engineering, Zhejiang University, Hangzhou 310027, China.
authors.forename: Di
authors.initials: D
authors.lastname: Nan
authors.affiliation: State Key Laboratory of Modern Optical Instrumentation, College of Optical Science and Engineering, Zhejiang University, Hangzhou 310027, China.
authors.forename: Weidong
authors.initials: W
authors.lastname: Shen
authors.affiliation: State Key Laboratory of Modern Optical Instrumentation, College of Optical Science and Engineering, Zhejiang University, Hangzhou 310027, China.
authors.forename: Yue
authors.initials: Y
authors.lastname: Fang
authors.affiliation: Institute of VLSI Design, Zhejiang University, Hangzhou 310027, China.
authors.forename: Lenian
authors.initials: L
authors.lastname: He
authors.affiliation: State Key Laboratory of Modern Optical Instrumentation, College of Optical Science and Engineering, Zhejiang University, Hangzhou 310027, China.
authors.forename: Xu
authors.initials: X
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Modern Optical Instrumentation, College of Optical Science and Engineering, Zhejiang University, Hangzhou 310027, China.
authors.forename: Qing
authors.initials: Q
authors.lastname: Yang