Local and Nonlocal Excitations in Cu 4p-1s Resonant X-Ray Emission Spectra of Nd 2CuO 4
Local and Nonlocal Excitations in Cu 4p-1s Resonant X-Ray Emission Spectra of Nd 2CuO 4
复制标题
Nd 2CuO 4 Cu 4p-1s 共振 X 射线发射光谱中的局域和非局域激发
DOI：
10.1143/jpsj.68.3100
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发表时间：
1999
影响因子：
1.7
通讯作者：
A. Kotani
中科院分区：
文献类型：
--
作者：
T. Idé;A. Kotani
从电子激发的局域性和非局域性出发，对Nd 2CuO 4的Cu 4p-1 s共振X射线发射谱（RXES）进行了理论研究.基于精确对角化技术，给出了杂质安德森模型和多Cu模型的详细分析。通过对偏态密度的研究，阐明了各激发态的基本性质。它表明，与实验数据的不一致是不可避免的杂质模型。解决这一难题的关键概念是RXES中间态的Zhang-Rice单态形成。我们发现，它生存在RXES的最低电荷转移激发的最终状态。强调了杂质模型的局限性和非局域激发在RXES中的重要作用。
Theoretical study for Cu 4 p -1 s resonant X-ray emission spectroscopy (RXES) of Nd 2 CuO 4 is given in the context of local and nonlocal natures of electronic excitations. Detailed analyses with an impurity Anderson model and multi-Cu models are presented, based on exact diagonalization technique. By investigating partial densities of states, basic characters of each excited state are clarified. It is demonstrated that a disagreement with experimental data is unavoidable with the impurity model. The key concept to solve the difficulty is Zhang-Rice singlet formation in the intermediate state of RXES. We find that it survives in the final state of RXES as the lowest charge-transfer excitation. The limitation of the impurity model and the essential role of nonlocal excitations in RXES are stressed.