Theory of X-ray Absorption Magnetic Circular Dichroism and Resonant X-ray Emission Spectra for Mixed Valence Rare-earth Compounds in High Magnetic Fields

用杂质Anderson模型建立了混合价稀土化合物在强磁场下的X射线吸收磁二色谱(XMCD)理论，并对日本最近发展起来的脉冲强磁场XMCD谱的实验数据进行了分析。考虑到YbInCu4的场致价态跃迁，我们首先分析了YbInCu4的Yb L边2，3&gt；的硬X射线XMCD谱的场依赖关系，然后利用YbAgCu4的电四极跃迁成功地归属了YbAgCu4的XMCD。最近，我们成功地分析了EuNi2(Si&lt；0.18&gt；Ge&lt；0.82&gt；)2.最后，我们对共振X射线发射光谱(RXES)进行了计算，为将来的强磁场下的RXES实验做了准备。

We constructed the theory of X-ray absorption magnetic circular dichroism (XMCD) of mixed-valence rare-earth compounds in high magnetic field with the impurity Anderson model, and analyzed experimental data of XMCD spectra measured by pulsed high magnetic field which was developed recently in Japan. We first analyzed the field dependence of hard X-ray XMCD spectra by electric dipole transition at the Yb L_<2,3>edges of YbInCu_4,taking into account the field-induced valence transition of the first order, and then succeeded in assigning the XMCD by the electric quadrupole transition for YbAgCu_4. More recently, we analyzed successfully the soft X-ray XMCD experimental data at the Eu M_<4,5>edges of EuNi_2(Si_<0.18>Ge_<0.82>)_2. Finally, we made some calculations of resonant X-ray emission spectroscopy (RXES), aiming at future RXES experiments in high magnetic fields.