title: Convolution Operations on Coding Metasurface to Reach Flexible and Continuous Controls of Terahertz Beams.
abstract: The concept of coding metasurface makes a link between physically metamaterial particles and digital codes, and hence it is possible to perform digital signal processing on the coding metasurface to realize unusual physical phenomena. Here, this study presents to perform Fourier operations on coding metasurfaces and proposes a principle called as scattering-pattern shift using the convolution theorem, which allows steering of the scattering pattern to an arbitrarily predesigned direction. Owing to the constant reflection amplitude of coding particles, the required coding pattern can be simply achieved by the modulus of two coding matrices. This study demonstrates that the scattering patterns that are directly calculated from the coding pattern using the Fourier transform have excellent agreements to the numerical simulations based on realistic coding structures, providing an efficient method in optimizing coding patterns to achieve predesigned scattering beams. The most important advantage of this approach over the previous schemes in producing anomalous single-beam scattering is its flexible and continuous controls to arbitrary directions. This work opens a new route to study metamaterial from a fully digital perspective, predicting the possibility of combining conventional theorems in digital signal processing with the coding metasurface to realize more powerful manipulations of electromagnetic waves.
authors.affiliation: State Key Laboratory of Millimeter Waves Southeast University Nanjing 210096 China; Synergetic Innovation Center of Wireless Communication Technology Southeast University Nanjing 210096 China.
authors.forename: Shuo
authors.initials: S
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Millimeter Waves Southeast University Nanjing 210096 China; Cooperative Innovation Centre of Terahertz Science No.4, Section 2, North Jianshe Road Chengdu 610054 China.
authors.forename: Tie Jun
authors.initials: TJ
authors.lastname: Cui
authors.affiliation: State Key Laboratory of Millimeter Waves Southeast University Nanjing 210096 China; Synergetic Innovation Center of Wireless Communication Technology Southeast University Nanjing 210096 China.
authors.forename: Lei
authors.initials: L
authors.lastname: Zhang
authors.affiliation: Center for Terahertz Waves and College of Precision Instrument and Optoelectronics Engineering Tianjin University Tianjin 300072 China.
authors.forename: Quan
authors.initials: Q
authors.lastname: Xu
authors.affiliation: Center for Terahertz Waves and College of Precision Instrument and Optoelectronics Engineering Tianjin University Tianjin 300072 China.
authors.forename: Qiu
authors.initials: Q
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Millimeter Waves Southeast University Nanjing 210096 China; Synergetic Innovation Center of Wireless Communication Technology Southeast University Nanjing 210096 China.
authors.forename: Xiang
authors.initials: X
authors.lastname: Wan
authors.affiliation: Center for Terahertz Waves and College of Precision Instrument and Optoelectronics Engineering Tianjin University Tianjin 300072 China.
authors.forename: Jian Qiang
authors.initials: JQ
authors.lastname: Gu
authors.affiliation: State Key Laboratory of Millimeter Waves Southeast University Nanjing 210096 China; Synergetic Innovation Center of Wireless Communication Technology Southeast University Nanjing 210096 China.
authors.forename: Wen Xuan
authors.initials: WX
authors.lastname: Tang
authors.affiliation: State Key Laboratory of Millimeter Waves Southeast University Nanjing 210096 China; Synergetic Innovation Center of Wireless Communication Technology Southeast University Nanjing 210096 China.
authors.forename: Mei
authors.initials: M
authors.lastname: Qing Qi
authors.affiliation: Center for Terahertz Waves and College of Precision Instrument and Optoelectronics Engineering Tianjin University Tianjin 300072 China.
authors.forename: Jia Guang
authors.initials: JG
authors.lastname: Han
authors.affiliation: Cooperative Innovation Centre of Terahertz Science No.4, Section 2, North Jianshe Road Chengdu 610054 China; Center for Terahertz Waves and College of Precision Instrument and Optoelectronics Engineering Tianjin University Tianjin 300072 China.
authors.forename: Wei Li
authors.initials: WL
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Millimeter Waves Southeast University Nanjing 210096 China; Jiangsu Xuantu Technology Co. Ltd 12 Mozhou East Road Nanjing 211111 China.
authors.forename: Xiao Yang
authors.initials: XY
authors.lastname: Zhou
authors.affiliation: State Key Laboratory of Millimeter Waves Southeast University Nanjing 210096 China; Cooperative Innovation Centre of Terahertz Science No.4, Section 2, North Jianshe Road Chengdu 610054 China.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Cheng
keywords: Fourier transform; coding metasurface; convolution theorem; scattering‐pattern shift; terahertz