Summary: | 碩士 === 國立中正大學 === 物理所 === 98 === Using a combination of low-energy electron diffraction (LEED) and Magneto-optic Kerr effect (MOKE), the surface lattice structure and magnetic property of the O-CoxNi1-x/Cu (001) and CoxNi1-x/O-Cu (001) have been studied. The spin reorientation transition will be forward to ~3ML on O- Co0.06Ni¬0.94 /Cu(001) by exposing 50L O2 . The LEED pattern of O- Co0.06Ni¬0.94 /Cu(001) and Co0.06Ni¬0.94 / O-Cu(001) is c(2×2) which represents the adsorption of O2 on Co0.06Ni¬0.94 . The oxygen is found always on top of the films, as expected for surfactants, LEED pattern is blurred after exposing oxygen for 100 L. the surface is supposed to non-ferromagnetism, The interlayer distance changes form~1.72Å to 1.87Å with oxygen exposure so that we know the surface have a lot of O2. Interlayer distance on surface is affected by lattice structure and magnetic property. Additionally, SRT happens in lower coverage by the introduction of oxygen. These results reveal that SRT of oxygen plays a crucial role on the surface structure and magnetic property.
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