Study On Dynamics Of Microelectromechanical Systems Under Multifield Coupling

With the rapid development of MEMS systems,micro/nano motors have become increasingly important.Micro/nano motors can convert different energy sources into mechanical energy,thereby driving the operation of MEMS systems.Among these different energy sources,light energy has attracted widespread attention due to its advantages of renewable,contactless,and remote manipulation.In this paper,we combine the interference of light on the surface of a magnet with the optical magnetic effect to successfully achieve the vibration of a suspended micro/nano graphite sheet driven by light.The main mechanism is that the interference of light on the surface of the magnet will form a periodically distributed light field in space,which makes the light absorption of the graphite sheet suspended at different positions on the magnet surface inconsistent.Different light absorption results in changes in the temperature and magnetic permeability of the graphite sheet,forming a periodic driving force that drives the vibration of the graphite sheet.The numerical results show that the amplitude of the graphite sheet can be close to 2microns,and the amplitude can be further increased with the increase of the control light wavelength and light power.The vibration frequency can be greater than 50 Hz,and it can also move normally with high damping.This oscillator has a simple structure,can work normally under uniform illumination of continuous light,and is a suspension structure with low dissipation.Therefore,it will have important application prospects in light energy conversion systems and MEMS.At the same time,this paper further studies the micro/nano motor in the terahertz wave band.It is found that due to the longer terahertz wave length and the larger force path of the periodic driving force field formed by interference,the amplitude is one order of magnitude larger than that driven by visible light.In addition,due to the longer wavelength,the number of complete standing wave periods that graphite spans during vibration is smaller,similar to the corresponding principle in quantum theory.Crossing a smaller number of periods causes its vibration to exhibit pseudoquantization,and its amplitude exhibits a discontinuous discretization curve.And by changing the intensity of terahertz waves,they can transition between different pseudo quantum states.Therefore,this terahertz wave driven vibration of micro/nano graphite sheets can not only provide a larger amplitude electromagnetic wave drive motor,but also serve as a research platform for quantum properties.