Exchange interactions in iron and nickel: DFT+DMFT study in paramagnetic phase

التفاصيل البيبلوغرافية
العنوان: Exchange interactions in iron and nickel: DFT+DMFT study in paramagnetic phase
المؤلفون: Katanin, A. A., Belozerov, A. S., Lichtenstein, A. I., Katsnelson, M. I.
المصدر: Phys. Rev. B 107, 235118 (2023)
سنة النشر: 2022
المجموعة: Condensed Matter
مصطلحات موضوعية: Condensed Matter - Strongly Correlated Electrons, Condensed Matter - Materials Science
الوصف: We analyze possible ways to calculate magnetic exchange interactions within the density functional theory plus dynamical mean-field theory (DFT+DMFT) approach in the paramagnetic phase. Using the susceptibilities obtained within the ladder DMFT approach together with the random phase approximation result for the Heisenberg model, we obtain bilinear exchange interactions. We show that the earlier obtained result of Stepanov et al. [Phys. Rev. Lett. 121, 037204 (2018); Phys. Rev. B 105, 155151 (2022)] corresponds to considering individual magnetic moments in each orbital in the leading-order approximation in the non-local correlations. We consider a more general approach and apply it to evaluate the effective magnetic parameters of iron and nickel. We show that the analysis, based on the inverse orbital-summed susceptibilities, yields reasonable results for both, weak and strong magnets. For iron we find, in the low-temperature limit, the exchange interaction $J_0\simeq 0.20$ eV, while for nickel we obtain $J_0\simeq 1.2$ eV. The considered method also allows one to describe the spin-wave dispersion at temperatures $T\sim T_C$, which is in agreement with the experimental data.
Comment: 10+3 pages, 6+5 figures
نوع الوثيقة: Working Paper
DOI: 10.1103/PhysRevB.107.235118
URL الوصول: http://arxiv.org/abs/2212.09267
رقم الأكسشن: edsarx.2212.09267
قاعدة البيانات: arXiv
الوصف
DOI:10.1103/PhysRevB.107.235118