镍金属的光电子光谱研究(英文)

Photoemission Studies of Metallic Nickel

光电子光谱实验对许多材料物理性质的理论解释给予了验证 .对于镍金属的电导性与磁场性质给出了实验上的解释 .通过试验 ,清楚的看出镍金属的 3d- 4s杂化及其非常高的 3d态密度 .由于杂化使得 3d带的空穴参与了导电过程 ,而高的态密度使其具有极高的有效质量 .这些发现都对镍金属弱导电性的理论解释做了支持 .此外 ,从自旋 -极化光电子光谱实验也显示了理论上对铁磁性本质解释—分子场 (交换场 )的存在 .并讨论实验与理论结果的差异 .

Photoemission experiments have been used to verify theoretical explanation for physical properties of many materials. For example, interesting properties of metallic nickel, i.e. seemingly contradictory nature between electrical conduction and magnetism, which is studied in this paper, could be explained by photoemission experiments. Through photoemission experiments, the 3d-4s hybridization and very high density of 3d states can be demonstrated clearly. The hybridization results in the contribution of 3d holes to electrical conductivity and the high density of state gives rise to a very high effective mass. These findings verify theoretical explanation for poor electrical conductivity of metallic nickel. In addition, spin-polarized photoemission shows the existence of molecular field, which is the theoretical essence for ferromagnetism. The discrepancies between experimental and theoretical results are also discussed in this paper.