标题：A variational size-dependent model for electrostatically actuated NEMS incorporating nonlinearities and Casimir force
作者：Liang, Binbin; Zhang, Long; Wang, Binglei; Zhou, Shenjie
作者机构：[Liang, Binbin; Zhang, Long; Wang, Binglei] Shandong Univ, Sch Civil Engn, Jinan 250061, Peoples R China.; [Wang, Binglei] Xi An Jiao Tong Univ, Sch 更多
通讯作者地址：[Wang, BL]Shandong Univ, Sch Civil Engn, Jinan 250061, Peoples R China.
来源：PHYSICA E-LOW-DIMENSIONAL SYSTEMS & NANOSTRUCTURES
关键词：Casimir force; Detachment length; Minimum gap; Size effect; NEMS
摘要：A size dependent model for the electrostatically actuated Nano-Bectro-Mechanical Systems (NEMS) incorporating nonlinearities and Casimir force is presented by using a variational method. The governing equation and boundary conditions are derived with the help of strain gradient elasticity theory and Hamilton principle. Generalized differential quadrature (GDQ) method is employed to solve the problem numerically. The pull in instability with Casimir force included is then studied. The results reveal that Casimir force, which is a spontaneous force between the two electrodes, can reduce the external applied voltage. With Casimir force incorporated, the pull in instability occurs without voltage applied when the beam size is in nanoscale. The minimum gap and detachment length can be calculated from the present model for different beam size, which is important for NEMS design. Finally, discussions of size effect induced by the strain gradient terms reveal that the present model is more accurate since size effect play an important role when beam in nanoscale. (C) 2015 Elsevier B.V. All rights reserved