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The temperature dependence of the magnetic anisotropy is an important aspect of the behavior of magnetic systems,and has been widely studied in bulk systems as well as in ultrathin films[1].In particular,Callen and Callens theory predicts that uniaxial anisotropies decrease with temperature as Ms3(t),while cubic anisotropies decrease up to Ms10(t).Where Ms(t)is the temperature-dependent saturation magnetization of the material[2].On the other hand,the temperature dependence of the magnetic anisotropy has not been studied experimentally,especially for the ultrathin iron films in the vicinal Si(111)substrate.Recently,Ye Jun et al carried out the anisotropic magnetoresistance(AMR)measurements in ultrathin single crystalline Fe film and proved that AMR is ideal probe of magnetic anisotropy constants [3].In this work,Fe single crystal film with 60 monolayer thickness was fabricated on vicinal Si(111)with about 0.1° miscut towards [11-2] direction using ultrathin p(2χ2)iron silicide as buffer layer.The structure and surface morphology were characterized through the LEED and STM.The magnetic and transport property were investigated through ex-situ MOKE and AMR.The results show that the sample exhibits in-plane uniaxial anisotropy that is about 1.1×103J/m3 got through fitting of hard axis loop by using coherent rotation model.The resistance of the film decrease linearly with the decreasing of temperature.It conforms to the metals general property.The coercive force in easy axis increases with the decreasing of temperature as T1/2 and can be explained by the theory proved by V.ZABLOTSKII,et al[4].Meanwhile we research the temperature dependence of the magnetic anisotropy among 80~300K through the AMR measurements.The first-and uniaxial magnetic anisotropy constants of the films were obtained by fitting the AMR data.The results show that the fourfold in-plane magnetic anisotropy(K1)and step-induced uniaxial anisotropy(KU)decrease with temperature through 80K to 300K.The relationship between magnetic anisotropy and temperature in this system is similar with the Callens theory predicts.At last we simply analysis the results from the relationship between temperature and crystal filed.