NiO/FeCo磁性多层膜的高频磁性研究

Relation between microwave complex permeability and ferromagnetic FeCo layer thickness in NiO/FeCo exchange-coupled film

制备了一系列具有铁磁/反铁磁交换偏置作用的[NiO/Fe65Co35]10多层膜,使用振动样品磁强计(VSM)测量了样品的静磁参数,利用微带线法测量了样品4GHz-10GHz的磁谱,首次制备并测得了自然共振频率(fr)在6GHz以上,最高到fr=9.6GHz的薄膜样品。结果表明交换偏置场(Hex)、各向异性场(Hua)、以及矫顽力(Hc)随铁磁层厚度(tFM)增大而减小;基于Landau-Lifishitz(L-L)方程对静磁参量和磁谱进行了比较,发现样品自然共振频率较L-L方程计算值偏大30%以上。

[ NiO/Fe65Co35 ] 10 exchange- coupled multilayer fihns for high frequency applications are fabricated, and their microwave permeability is systematic studied. Both exchange bias field and ferromagnetic resonance frequency increase with decreasing Fe65Co35 thickness. The microwave properties such as permeability and FMR frequency can be controlled by changing Fe65Co35 thickness. Ferromagnetic resonance frequencies beyond 6 GHz are measured and reported for the first time.