Dynamical Coherent-Potential Approximation and Tight-Binding Linear Muffintin Orbital Approach to Correlated Electron System(Condensed matter: electronic structure and electrical, magnetic, and optical properties)
Dynamical Coherent-Potential Approximation and Tight-Binding Linear Muffintin Orbital Approach to Correlated Electron System(Condensed matter: electronic structure and electrical, magnetic, and optical properties)
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DOI：
10.1143/jpsj.77.094706
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发表时间：
2008-08
影响因子：
1.7
通讯作者：
Y. Kakehashi;T. Shimabukuro;Toshihito Tamashiro;Tetsuro Nakamura
中科院分区：
文献类型：
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作者：
Y. Kakehashi;T. Shimabukuro;Toshihito Tamashiro;Tetsuro Nakamura
将关联电子的动力学相干势近似（CPA）推广到由第一性原理紧束缚线性Muffintin轨道（LMTO）带和原子内库仑相互作用组成的具有真实哈密顿量的体系.基于泛函积分方法和忽略不同频率的动力学势之间模-模耦合的调和近似，得到了热力学势和绿色函数的自洽方程。对Fe和Ni在静态近似下进行了二阶动力学修正的数值计算。在有限温度下得到了Ni的准粒子态和6 eV伴子的带窄化。该理论导致了铁和镍的居里-外斯定律。计算出的有效玻尔磁子数为3.0 µ B（Fe）和1.2 µ B（Ni），解释了实验数据。但计算的居里温度为2020 K的铁和1260 K的镍，是...
Dynamical coherent-potential approximation (CPA) to correlated electrons has been extended to a system with realistic Hamiltonian which consists of the first-principles tight-binding linear muffintin orbital (LMTO) bands and intraatomic Coulomb interactions. Thermodynamic potential and self-consistent equations for Green function are obtained on the basis of the functional integral method and the harmonic approximation which neglects the mode–mode couplings between the dynamical potentials with different frequency. Numerical calculations have been performed for Fe and Ni within the second-order dynamical corrections to the static approximation. The band narrowing of the quasiparticle states and the 6 eV satellite are obtained for Ni at finite temperatures. The theory leads to the Curie–Weiss law for both Fe and Ni. Calculated effective Bohr magneton numbers are 3.0 µ B for Fe and 1.2 µ B for Ni, explaining the experimental data. But calculated Curie temperatures are 2020 K for Fe and 1260 K for Ni, being ...