AN ANALYSIS ON CHARACTERISTIC OF MAGNETOELASTICITY OF A MAGNETIC FIELD MICROSENSOR MADE OF CANTILEVERED PLATES WITH FERROMAGNETIC FILMS

The purpose of this paper is to study the magnetomechanicalcharacteristic of a microsensor which is composed of a cantileveredbeam-plate with ferromagnetic films in order to measure the magneticfield from the deformation of plate when the microsensor is locatedin the magnetic field. To this end, a nu- merical approach made up ofthe finite element method for magnetic field and the finitedifference method for deflection of the microsensor is proposed toperform the numerical analysis of deflection under magnetoelasticinteraction. Some quantitative results of a case study for themagnetoelastic characteristic between the mag- netic field anddeflection of the microsensor in the magnetic field are given. Theresults show that this mi- crosensor can be used not only to measurethe magnitude of magnetic intensity, but also to possibly monitor thedirection of the vector of the magnetic field.

Room-temperature ferromagnetism induced by Cu vacancies in Cu_x(Cu_2O)_(1-x) granular films

Cux（Cu2O）1-x（0.09 x 1.00） granular films with thickness about 280 nm have been fabricated by direct current reactive magnetron sputtering. The atomic ratio x can be controlled by the oxygen flow rate during Cux（Cu2O）1-x deposition. Room-temperature ferromagnetism（FM） is found in all of the samples. The saturated magnetization increases at first and then decreases with the decrease of x. The photoluminescence spectra show that the magnetization is closely correlated with the Cu vacancies in the Cux（Cu2O）1-x granular films. Fundamentally, the FM could be understood by the Stoner model based on the charge transfer mechanism. These results may provide solid evidence and physical insights on the origin of FM in the Cu2O-based oxides diluted magnetic semiconductors, especially for systems without intentional magnetic atom doping.

The structure and magnetic properties of β-(Ga_(0.96)Mn_(0.04))_2O_3 thin film

High quality epitaxial single phase（Ga_（0.96）Mn_（0.04））_2O_3 and Ga_2O_3 thin films have been prepared on sapphire substrates by using laser molecular b（eam）epitaxy（L-MBE）. X-ray diffraction results indicate that the thin films have the monoclinic structure with a 201 preferable orientation. Room temperature（RT） ferromagnetism appears and the magnetic properties of β-（Ga_（0.96）Mn_（0.04））_2O_3 thin film are enhanced compared with our previous works. Experiments as well as the first principle method are used to explain the role of Mn dopant on the structure and magnetic properties of the thin films. The ferromagnetic properties are explained based on the concentration of transition element and the defects in the thin films.

Skyrmion-(non)crystal structure stabilized by dipolar interaction

We report a numerical study on the role of longrange dipolar interaction played on the creation and stabilization of skyrmion-(non)crystal structure in chiral ferromagnetic thin films without any anisotropies,based on a Monte-Carlo simulation method.With the increase of external magnetic field,the microscopic spin configuration is transformed from a spin-spiral stripe or labyrinth structure,depending on the strength of dipolar interaction,into a skyrmion-(non)crystal structure,and then into a skyrmiongas structure,and finally into a ferromagnetic state.Interestingly,with the increase of dipolar interaction,the skyrmion-crystal structure evolves from a triangular arrangement into a square arrangement with the change of skyrmion shape from circle to square.For larger dipolar interactions,the skyrmion-crystal structure loses the regular arrangements and the skyrmions,remaining topological,exhibit different shapes and sizes and squeeze with each other,whose distributions are analogous to a non-crystal structure.Therefore,different skyrmion-(non)crystal structures are stabilized in different ranges of dipolar interactions,which further promotes the applications of skyrmions as non-volatile information carriers.