Study On The Kinetic Characteirstics Of Micro-/Nano-Magnetic Composite Cantilevers

Static deformation and dynamic vibration of micro and nano-cantilever is one of the most interesting issues of MEMS, and it can be used as the core component of the oscillator and resonator in transducer device. The vibration of the micro-/nano-cantilever can be excited through a variety of driving forces. The vibration of micro-/nano-cantilever consisting of magnetostrictive film and substrate can be excited through magnetic-elastic coupling force driven by the external alternating magnetic field superimposed on a static field. On the basis of the general solution, we study the ferromagnetic resonance (FMR) of the system, the intensity and the direction dependence of the ferromagnetic resonance frequency on the static field. As a result, it is find that the one can obtain a low frequency FMR near the spin reorientation transition, moreover, the jump of magnetization at the spin reorientation transition induces a large flexion and torsion deformation, and it may be a characteristic with important applications. We further calculate the low frequency magnetization as a function of static field intensity and the direction. And we also study the possibility of producing mechanical resonance of the cantilever through modulating the external static field when the uniaxial magnetic film is under FMR. We find that the eigen modes of the mechanical resonance can be excited by modulating the static magnetic field when the cantilever with small geometry and its mechanical resonance frequency is large enough. For the case of larger cantilevers with small resonance frequency, it is also possible the excited the eigen modes near the spin reorientation transition. The results can be served as a reference for characterizing and the measuring of the basic physical properties of the magnetic micro-/nano vibration structure and the design and application of magnetostriction-based microelectromechanical system.