Nonlinear pull-in instability of suspended graphene-based sensors
Nonlinear pull-in instability of suspended graphene-based sensors
复制标题
悬浮石墨烯传感器的非线性拉入不稳定性
DOI：
10.1209/0295-5075/125/20011
复制
发表时间：
2019-02
期刊：
影响因子：
1.8
通讯作者：
Meng Guang
中科院分区：
文献类型：
--
作者：
Hu Kai-Ming;Zhang Wen-Ming;Yan Han;Peng Zhi-Ke;Meng Guang
在石墨烯表面施加外电场是提高石墨烯分子吸附能力的重要途径，因此悬浮石墨烯传感器的吸合不稳定性成为一个关键问题。在考虑残余内建应变、边缘场和分子间力的基础上，建立了一个描述悬浮式石墨烯传感器非线性吸合行为的机电模型。吸合电压的计算结果与文献报道的实验数据吻合较好。此外，石墨烯传感器的断裂失效最初与拉入失效进行比较。为了避免拉入失稳和断裂失效，推导了悬臂式和扶手椅式石墨烯传感器轴向预应力的临界公式。研究表明，轴向预应力是提高石墨烯传感器吸合稳定性的一种有效且可控的方法。
Applying an external electric field on a graphene surface is an important way to improve the molecular adsorption capability of graphene, thus pull-in instability of suspended graphene sensors becomes a critical issue. Incorporating residual built-in strains, fringing fields and intermolecular forces, an electromechanical model is developed to characterize the nonlinear pull-in behaviors of suspended graphene-based sensors. The obtained results of pull-in voltages agree well with the reported experimental data. Moreover, the fracture failure of graphene sensors is initially compared to the pull-in failure. To avoid pull-in instability and fracture failure, critical formulas of axial pre-stress for zigzag-oriented and armchair-oriented graphene sensors are derived. It is demonstrated that axial pre-stress is an effective and controllable way to improve the pull-in stability of graphene sensors.