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DOE OSTI Β· 3387225

Derivation of low-energy Hamiltonians for heavy-fermion materials

Ghioldi, E. A. [Univ. of Tennessee, Knoxville, TN (United States)]Β·Wang, Zhentao [Zhejiang Univ., Hangzhou (China)] (ORCID:0000000174422933)Β·Chinellato, L. M. [Univ. of Tennessee, Knoxville, TN (United States)] (ORCID:0009000789544248)Β·Zhu, Jian-Xin [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000179913918)Β·Nomura, Yusuke [Tohoku Univ., Sendai (Japan)] (ORCID:000000034956562X)Β·Arita, Ryotaro [Univ. of Tokyo (Japan); RIKEN Center for Emergent Matter Science (CEMS), Wako (Japan)] (ORCID:000000015725072X)Β·Simeth, W. [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Univ. of Zurich (Switzerland)]Β·Janoschek, M. [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Univ. of Zurich (Switzerland); Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)]Β·Ronning, Filip [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000226797957)Β·Batista, Cristian D. [Univ. of Tennessee, Knoxville, TN (United States); Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)] (ORCID:0000000316673667)
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Abstract

Here, by utilizing a multiorbital periodic Anderson model with parameters obtained from ab initio band structure calculations, combined with degenerate perturbation theory, we derive effective Kondo-Heisenberg and spin Hamiltonians that capture the interaction among the effective magnetic moments. This derivation encompasses fluctuations via both nonmagnetic 4⁒𝑓 0 and magnetic 4⁒𝑓 2 virtual states, and its accuracy is confirmed through comparison with experimental data obtained from CeIn 3 . The significant agreement observed between experimental results and theoretical predictions underscores the potential of deriving minimal models from first-principles calculations for achieving a quantitative description of 4⁒𝑓 materials. Moreover, our microscopic derivation unveils the underlying origin of anisotropy in the exchange interaction between Kramers doublets, shedding light on the conditions under which this anisotropy may be weak compared to the isotropic contribution.

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75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITYKondo effectdensity functional theoryheavy-fermion systemsmagnetic systemsmagnetismmetals

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Ghioldi, E. A. [Univ. of Tennessee, Knoxville, TN (United States)], Wang, Zhentao [Zhejiang Univ., Hangzhou (China)] (ORCID:0000000174422933), Chinellato, L. M. [Univ. of Tennessee, Knoxville, TN (United States)] (ORCID:0009000789544248), Zhu, Jian-Xin [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000179913918), Nomura, Yusuke [Tohoku Univ., Sendai (Japan)] (ORCID:000000034956562X), Arita, Ryotaro [Univ. of Tokyo (Japan); RIKEN Center for Emergent Matter Science (CEMS), Wako (Japan)] (ORCID:000000015725072X), Simeth, W. [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Univ. of Zurich (Switzerland)], Janoschek, M. [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Univ. of Zurich (Switzerland); Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)], Ronning, Filip [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000226797957), Batista, Cristian D. [Univ. of Tennessee, Knoxville, TN (United States); Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)] (ORCID:0000000316673667). 2024-11-08. Derivation of low-energy Hamiltonians for heavy-fermion materials. https://doi.org/10.1103/physrevb.110.195123

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75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY subjectDensity functional theory subjectMagnetism subject

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