Electromagnetic instability analysis of functionally graded tapered nano-tweezers

Abstract

Abstract Increasing the application of electromechanical nano-tweezers for biological purposes results in new operating conditions such as an external magnetic field. This study deals with investigating the electromagnetic instability of nano-wire manufactured tweezers. To enhance the nano-tweezers’ operating range, a pair of functionally graded nano-wire-based tweezers with linearly varying diameter is considered. The impact of Lorentz forces due to external magnetic flux is simulated by developing Maxwell’s equation. The material distribution along the length of the nano-tweezers arms is modeled based on the power-law distribution. The size-dependent nonlinear constitutive equation of the system is extracted by employing the couple stress theory in combination with Hamilton’s principle. A finite element procedure is proposed to simulate the nano-system and investigate electromechanical instability behavior. The role of influential parameters, including the external magnetic field, the size dependency, material distribution, the Casimir force, and the geometry on the tweezering range and instability voltage of nano-tweezers, are investigated.