摘要
We examine the electromechanical field and charge redistribution within a flexoelectric semiconductor(FS)nanobeam,accounting for bending,fundamental thickness-shear,and antisymmetric thickness-stretch deformations.The coupled gov-erning equations include microstructure,flexoelectric,and semiconductor effects,highlighting the interplay between me-chanical displacement,electric potential,and charge carriers.For applications in flexoelectronic devices,the static bending of a simply supported FS beam induced by uniform pressure and wave propagation in an unbounded FS beam are analytically addressed using the derived framework.The effects of antisymmetric thickness-stretch on mechanical displacements and electron concentration perturbation,as well as size dependence of microstructure and flexoelectric effects,are identified.An interesting finding reveals that wave frequencies of the antisymmetric thickness-stretch mode,as anticipated by the proposed model,are larger compared to those of the model neglecting flexoelectric and semiconductor effects.For the first time,the cutoff frequency of antisymmetric thickness-stretch impacted by the two features is explained mathematically.These findings are beneficial for enhancing the performance of flexoelectronic sensors and electroacoustic devices.
本文研究了在考虑弯曲、基本厚度剪切和反对称厚度伸缩变形情况下挠曲电半导体纳米梁中的机电耦合效应和电荷重分布问题.所耦合的控制方程涵盖了微结构效应、挠曲电效应和半导体效应,强调了机械位移、电势和载流子之间的相互耦合作用.为便于挠曲电电子设备应用,本文在所推导理论框架基础上解析求解了由均匀压力引起的挠曲电半导体简支梁的静态弯曲以及无限长挠曲电半导体梁的波传播问题.特别是,本文探讨了反对称厚度伸缩对机械位移和电子浓度扰动的影响,揭示了微结构和挠曲电效应的尺寸依赖性.研究发现,与忽略挠曲电和半导体效应的模型相比,反对称厚度伸缩波的频率更高,本文首次从数学角度解释了这些效应对反对称厚度伸缩波截止频率的影响.这些发现为提高挠曲电传感器和电声设备的性能提供了理论依据.
基金
supported by the National Natural Science Foundation of China(Grant No.12002086(Gongye Zhang))
Fundamental Research Funds for the Central Universities(Grant No.2242022R40040(Gongye Zhang))
Postgraduate Research&Practice Innovation Program of Jiangsu Province(Grant No.KYCX24_0365(Ziwen Guo)).
