http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Ni/Fe(001)의 자성과 자기이방성에 대한 제일원리계산
권오룡(Oryong Kwon),홍순철(Soon Cheol Hong) 한국자기학회 2015 韓國磁氣學會誌 Vol.25 No.4
Recent theoretical calculations predicted that a system composed exclusively of 3d transition metals without 4d/5d transition metals or rare earth metals can have strong perpendicular magnetocrystalline anisotropy (MCA) if Fe and Ni layers are arranged appropriately. They considered only Fe-terminated surfaces, noting that Fe/MgO(001) and CoFeB/MgO(001) show strong perpendicular MCA. In this paper, we investigate magnetism and MCA of Ni/Fe(001) surface where Ni layer is positioned at the surface, by using complementarily the first principles calculational methods of Vienna Ab-initio Simulation Package (VASP) and Fullpotential Linearized Augmented Plane Wave (FLAPW) method. Comparing results of magnetism and MCA obtained by VASP with the results by FLAPW method, we find the VASP results do not show big difference from results by FLAPW method. Magnetic moments of Fe and Ni are enhanced due to strong hybridization between Fe and Ni bands. MCA of Ni/Fe(001) is parallel to the surface, which implies the surface termination plays a crucial role in determining MCA of a system.
Jekal, Soyoung,Kwon, Oryong,Hong, Soon Cheol,Lee, Jae Il American Scientific Publishers 2015 Journal of nanoscience and nanotechnology Vol.15 No.3
<P>A bulk d(0) NaN of rocksalt or zinc-blende structure was predicted to be a ferromagnetic half metal and furthermore the half-metallicity would be retained in thin films. Such half metallicity of d(0) ferromagnetic NaN is attractive for possible application in a spintronics device, such as a spin transfer torque magnetic random access memory. In this study, we carried out first-principles calculations on magnetocrystalline anisotropy rocksalt structured NaN thin films with different thicknesses, using Vienna Ab-initio Simulation Package code. It was found that the NaN(001) thin films have perpendicular magnetization with quite low magnetocrystalline anisotropy energies of order of 10 mu eV, but capping of a 5d-transition metal Ta monolayer over the NaN(001) thin films enhances the perpendicular magnetocrystalline anisotropy energies significantly, more than 10 times. Furthermore, the 1(Ta)/NaN(001) systems retain their half-metallicity except the NaN layer just below Ta.</P>