Search

Your search keyword '"Yuan, Xiao-Cong"' showing total 450 results
Start Over Author "Yuan, Xiao-Cong"
450 results on '"Yuan, Xiao-Cong"'

1. Effects of Fano resonance on optical chirality of planar plasmonic nanodevices

Author

Hwang, Yongsop, Lee, Seojoo, Kim, Sejeong, Lin, Jiao, and Yuan, Xiao-Cong

Subjects
Physics - Optics
Abstract

The effects of Fano resonance on the optical chirality of planar plasmonic nanodevices in the visible wavelength range are experimentally observed and theoretically explained. The nanodevice consists of a nanodisk at the center with six gold nanorods with an orientation angle to exhibit optical chirality under dark-field illumination. The chiral response induced by the gold nanorods are affected by the presence of the nanodisk with different diameters which causes Fano resonance. An intriguing change to the opposite selection preference of different handedness of the circularly polarized light has been clearly observed experimentally. This change of the preference is understood based on the extended coupled oscillator model. Moreover, electrostatic analysis and the time-dependent simulations provide a further understanding of the phenomenon. The observed and understood effects of Fano resonance on optical chirality enables effective manipulation of chiral characteristics of planar subwavelength nanodevices.

Published
2018
Full Text
View/download PDF

2. Optical chirality from dark-field illumination of planar plasmonic nanostructures

Author

Hwang, Yongsop, Hopkins, Ben, Wang, Dapeng, Mitchell, Arnan, Davis, Timothy J., Lin, Jiao, and Yuan, Xiao-Cong

Subjects
Physics - Optics
Abstract

Dark-field illumination is shown to make planar chiral nanoparticle arrangements exhibit circular dichroism in extinction analogous to true chiral scatterers. Circular dichrosim is experimentally observed at the maximum scattering of single oligomers consisting rotationally symmetric arrangements of gold nanorods, with strong agreement to numerical simulation. A dipole model is developed to show that this effect is caused by a difference in the geometric projection of a nanorod onto the handed orientation of electric fields created by a circularly polarized dark-field that is normally incident on a glass substrate. Owing to this geometric origin, the wavelength of the peak chiral response is also experimentally shown to shift depending on the separation between nanoparticles. All presented oligomers have physical dimensions less than the operating wavelength, and the applicable extension to closely packed planar arrays of oligomers is demonstrated to amplify the magnitude of circular dichroism. The realization of strong chirality in these oligomers demonstrates a new path to engineer optical chirality from planar devices using dark-field illumination.

Published
2017
Full Text
View/download PDF

3. Active sorting of orbital angular momentum states of light with cascaded tunable resonators

Author

Wei, Shibiao, Earl, Stuart K., Yuan, Xiao-Cong, Kou, Shan Shan, and Lin, Jiao

Subjects
Physics - Optics
Abstract

Light carrying orbital angular momentum (OAM) has been shown to be of use in a disparate range of fields ranging from astronomy to optical trapping, and as a promising new dimension for multiplexing signals in optical communications and data storage. A challenge to many of these applications is a reliable and dynamic method that sorts incident OAM states without altering them. Here we report a wavelength-independent technique capable of dynamically filtering individual OAM states based on the resonant transmission of a tunable optical cavity. The cavity length is piezo-controlled to facilitate dynamic reconfiguration, and the sorting process leaves both the transmitted and reflected signals in their original states for subsequent processing. As a result, we also show that a reconfigurable sorting network can be constructed by cascading such optical resonators to handle multiple OAM states simultaneously. This approach to sorting OAM states is amenable to integration into optical communication networks and has implications in quantum optics, astronomy, optical data storage and optical trapping.

Published
2017

5. Mode-matching metasurfaces: coherent reconstruction and multiplexing of surface waves

Author

Lin, Jiao, Wang, Qian, Yuan, Guanghui, Du, Luping, Kou, Shan Shan, and Yuan, Xiao-Cong

Subjects
Physics - Optics
Abstract

Metasurfaces are promising two-dimensional metamaterials that are engineered to provide unique properties or functionalities absent in naturally occurring homogeneous surfaces. Here, we report a type of metasurface for tailored reconstruction of surface plasmon waves from light. The design is generic in a way that one can selectively generate different surface plasmon waves through simple variation of the wavelength or the polarization state of incident light. The ultra-thin metasurface demonstrated in this paper provides a versatile interface between the conventional free-space optics and a two-dimensional platform such as surface plasmonics., Comment: 7 figures, supplementary information at the end of the document

Published
2014

32. Fast selective edge-enhanced imaging with topological chiral lamellar superstructures

Author

Chen, Wen, Zhu, Dong, Liu, Si-Jia, Zhang, Yi-Heng, Zhu, Lin, Li, Chao-Yi, Ge, Shi-Jun, Chen, Peng, Zhang, Wan-Long, Yuan, Xiao-Cong, and Lu, Yan-Qing

Abstract

Edge detection is a fundamental operation for feature extraction in image processing. The all-optical method has aroused growing interest owing to its ultra-fast speed, low energy consumption and parallel computation. However, current optical edge detection methods are generally limited to static devices and fixed functionality. Herein, we propose a fast-switchable scheme based on a ferroelectric liquid crystal topological structure. The self-assembled chiral lamellar superstructure, directed by the azimuthally variant photo-alignment agent, can be dynamically controlled by the polarity of the external electric field and respectively generates the vector beams with nearly orthogonal polarization distribution. Even after thousands of cycles, the horizontal and vertical edges of the object are selectively enhanced with an ultra-fast switching time of ∼57 μs. Broadband edge-enhanced imaging is efficiently demonstrated. This work extends the ingenious building of topological heliconical superstructures and offers an important glimpse into their potential in the emerging frontiers of optical computing for artificial intelligence.Topological chiral lamellar superstructures enable dynamic light manipulation and fast selective edge-enhanced imaging in a wide band.

Published
2024
Full Text
View/download PDF

39. Graphene-Based Optical Biosensor Using Functionalized Magnetic Nanoparticles

Author

孙立勋 Sun Lixun, 朱思伟 Zhu Siwei, 杨勇 Yang Yong, 吴晓静 Wu Xiao-jing, 张慧琴 Zhang Huiqin, 袁小聪 Yuan Xiao-cong, and 杨艺哲 Yang Yizhe

Subjects
Materials science, Graphene, law, Magnetic nanoparticles, Nanotechnology, Optical biosensor, Atomic and Molecular Physics, and Optics, Electronic, Optical and Magnetic Materials, law.invention
Published
2020

Catalog

Books, media, physical & digital resources
See catalog results