Typical transient effects in a piezoelectric semiconductor nanofiber under a suddenly applied axial time-dependent force  

作　　者：Wanli YANG Yuxing LIANG 

机构地区：[1]Department of Mechanics,School of Aerospace Engineering,Hubei Key Laboratory of Engineering Structural Analysis and Safety Assessment,Huazhong University of Science and Technology,Wuhan 430074,China

出　　处：《Applied Mathematics and Mechanics(English Edition)》2021年第8期1095-1108,共14页应用数学和力学（英文版）

基　　金：the National Natural Science Foundation of China(No.11972164);the Key Laboratory Project of Hubei Province of China(No.2016CFA073)。

摘　　要：Based on the mechanical motion equation,Gauss’s law,and the current continuity condition,we study a few typical transient effects in a piezoelectric semiconductor(PS)fiber to realize the startup and turning-off functions of common piezotronic devices.In this study,the transient extensional vibration induced by a suddenly applied axial time-dependent force is examined in a cantilevered n-type ZnO nanofiber.Neither the magnitude of the loadings nor the doping concentration significantly affects the propagation caused by disturbance of the axial displacement.However,both of the factors play an important role in the propagation caused by disturbance of the electron concentrations.This indicates that the electromechanical coupling effect can be expected to directly determine the electronic performance of the devices.In addition,the assumption of previous simplified models which neglect the charge carriers in Gauss’s law is discussed,showing that this assumption has a little influence on the startup state when the doping concentration is smaller than 1021 m-3.This suggests that the screening effect of the carriers on the polarized electric field is much reduced in this situation,and that the state is gradually transforming into a pure piezoelectric state.Nevertheless,the carriers can provide a damping effect,which means that the previous simplified models do not sufficiently describe the turning-off state.The numerical results show that the present study has referential value with respect to the design of newly multifunctional PS devices.

关 键 词：transient piezoelectric semiconductor(PS) extension vibration 

分 类 号：O472.91[理学—半导体物理]