Implementing fractional Fourier transform using SH0 wave computational metamaterials in space domain

• 作 者: LV ZengYao DING YuanShuai LI HangYu PEI YongMao
• 机 构: Department of Engineering Mechanics,Center for Flexible Electronics Technology,Applied Mechanics Lab
• 出 处: 中国科学：技术科学（英文版）
• 发表日期: 2021年11期

Through the design of artificial structures,metamaterials can control the incident wave in the sub-wavelength range to achieve functions that natural materials cannot achieve,such as high absorption,negative refraction,cloaking [1-3],asymmetric propagation [4,5],and holography [6-8].In re-cent years,the new concept of computational metamaterials[9-12] has opened up a new direction for analog computing,providing high-throughput,energy-free computing opera-tions for special computing tasks,including spatial integra-tion,derivative and convolution [11],time domain integration,derivative and Hilbert transform [13].In the spatial domain,some acoustic computing metamaterials [14]including integrators and differentiators have been im-plemented.However,the elastic wave computational meta-material lacks a design method to simultaneously modulate the phase and amplitude to control the elastic wave [15-17].Qiu et al.[18] proposed a metasurface consisting of multiple parallel strips with varied widths which can steer and focus SH0 wave in plates.They used the nature of the phase(group) velocity of the quasi-SH0 decreasing (increasing)with increasing strip width [19].Unfortunately,the ampli-tude of SH0 wave was in lack of consideration.