Zhuoma Wang¹, Ruoyan Li^2,3, Wenjing Ye^2,*, Yijun Liu³

The International Conference on Computational & Experimental Engineering and Sciences, Vol.27, No.4, pp. 1-2, 2023, DOI:10.32604/icces.2023.09236

Abstract An acoustic diffuser refers to a device that spreads sound energy uniformly in all directions. Such a device plays a very important role in architectural acoustics, i.e., concert halls and auditoriums. Many designs such as the wellknown Schroeder diffusers [1] have been proposed and developed throughout the past several decades. However, most of these conventional designs achieve uniform sound diffusion by using different air trenches to create a phase shift profile following a specific sequence such as maximum length sequence or quadratic residue sequence derived from the number theory [1,2]. As such, these diffusers have considerable thicknesses, which makes them… More >

Haoyi Cheng¹, Jingwen Guo¹, Wenjing Ye^1.*, Xin Zhang¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.26, No.2, pp. 1-1, 2023, DOI:10.32604/icces.2023.09237

Abstract With their thin thicknesses and unprecedent wave manipulation capabilities, acoustic metasurfaces have a great potential to be applied in a wide range of applications. Most existing metasurfaces are passive devices. Although passive devices are easy to implement and consume no energy, one major shortcoming of passive devices is their fixed and limited functionality, which greatly limits their application scope. To increase the functionalities of a metasurface and yet still maintain its passivity, we propose to use the wave frequency as a tuning freedom to realize multiple functionalities in one single passive device. Specifically, the passive metasurface will be designed to… More >

Haoran Wei, Tian Ji, Jianqing Huang^*

Journal of Renewable Materials, Vol.11, No.2, pp. 731-743, 2023, DOI:10.32604/jrm.2022.022283

Abstract Simultaneous broadband absorption and polarization conversion are crucial in many practical applications, especially in terahertz communications. Thus, actively tunable metamaterial systems can exploit the graphene-based nanomaterials derived from renewable resources because of the flexible surface conductivity and selective permeability of the nanomaterials at terahertz frequencies. In this paper, we propose a graphene-based active tunable bifunctional metasurface for dynamic terahertz absorption and polarization conversion. The graphene ring presents a certain opening angle (A) along the diagonal of the xoy plane. When A = 0°, the proposed metasurface behaves as a broadband absorber. Numerical results show the feasibility of achieving this polarization-insensitive… More >