First-Principles Theory of Momentum Dependent Local Ansatz Approach to Correlated Electron System

Abstract

We have extended the momentum-dependent local-ansatz (MLA) wavefunction method to the first-principles version using the tight-binding LDA+U Hamiltonian for the description of correlated electrons in the real system. The MLA reduces to the Rayleigh-Schrödinger perturbation theory in the weak correlation limit, and describes quantitatively the ground state and related low-energy excitations in solids. The theory has been applied to the paramagnetic Fe. The role of electron correlations on the energy, charge fluctuations, amplitude of local moment, momentum distribution functions, as well as the mass enhancement factor in Fe has been examined as a function of Coulomb interaction strength. It is shown that the inter-orbital charge-charge correlations between $d$ electrons make a significant contribution to the correlation energy and charge fluctuations, while the intra-orbital and inter-orbital spin-spin correlations make a dominant contribution to the amplitude of local moment and the mass enhancement in Fe. Calculated partial mass enhancements are found to be 1.01, 1.01, and 3.33 for $s$, $p$, and $d$ electrons, respectively. The averaged mass enhancement 1.65 is shown to be consistent with the experimental data as well as the recent results of theoretical calculations.

arXiv comment30 Pages, 6 figures

References in corpus (17)

• Electronic Structure Calculations with Dynamical Mean-Field Theory: A Spectral Density Functional Approach
• LDA+Gutzwiller Method for Correlated Electron Systems: Formalism and Its Applications
• About the strength of correlation effects in the electronic structure of iron
• Orbital selective local moment formation in iron: first principle route to an effective model
• Gutzwiller density functional calculations of the electronic structure of FeAs-based superconductors: Evidence for a three-dimensional Fermi surface
• Ab initio electronic structure calculation of correlated systems: EMTO-DMFT approach
• Impact of electronic correlations on the equation of state and transport in $\epsilon$-Fe
• Gutzwiller theory of band magnetism in LaOFeAs
• Electronic structure and effects of dynamical electron correlation in ferromagnetic bcc-Fe, fcc-Ni and antiferromagnetic NiO
• Atomic correlations in itinerant ferromagnets: quasi-particle bands of nickel
• First-Principles Dynamical Coherent-Potential Approximation Approach to the Ferromagnetism of Fe, Co, and Ni
• Local-Ansatz Approach with Momentum Dependent Variational Parameters to Correlated Electron Systems
• Momentum Dependent Local-Ansatz Approach to Correlated Electron Systems: Non Half-Filled Case
• Momentum Dependent Local-Ansatz Wavefunction from Weak to Strong Electron Correlations
• Momentum Dependent Local-Ansatz with Hybrid Wavefunction from Weak to Strong Electron Correlations
• Ferromagnetism of transition metals and screened exchange interactions
• Momentum-dependent local ansatz approach to correlated electrons

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• First-Principles Momentum Dependent Local Ansatz Approach to the Momentum Distribution Function in Iron-Group Transition Metals
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• Momentum-Dependent Local Ansatz Approach to the Metallic Ferromagnetism
• Correlated Electrons and Mass Enhancement on the Beta-Mn Type Lattice