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arXiv · 2012.08812

Magnetic Compton profiles of Ni beyond the one-particle picture: numerically exact and perturbative solvers of dynamical mean-field theory

A. D. N. James·M. Sekania·S. B. Dugdale·L. Chioncel
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Abstract

We calculated the magnetic Compton profiles (MCPs) of Ni using density functional theory supplemented by electronic correlations treated within dynamical mean-field theory (DMFT). We present comparisons between the theoretical and experimental MCPs. The theoretical MCPs were calculated using the KKR method with the perturbative spin-polarized T-matrix fluctuation exchange approximation DMFT solver, as well as with the full potential linear augmented planewave method with the numerically exact continuous-time quantum Monte Carlo DMFT solver. We show that the total magnetic moment decreases with the intra-atomic Coulomb repulsion $U$, which is also reflected in the corresponding MCPs. The total magnetic moment obtained in experimental measurements can be reproduced by intermediate values of $U$. The spectral function reveals that the minority X$_2$ Fermi surface pocket shrinks and gets shallower with respect to the density functional theory calculations.

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A. D. N. James, M. Sekania, S. B. Dugdale, L. Chioncel. 2020-12-16. Magnetic Compton profiles of Ni beyond the one-particle picture: numerically exact and perturbative solvers of dynamical mean-field theory. https://doi.org/10.1103/physrevb.103.115144

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