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arXiv · 2204.08675

Rigorous analysis of the effects of electron-phonon interactions on magnetic properties in the one-electron Kondo lattice model

Tadahiro Miyao·Kazuhiro Nishimata·Hayato Tominaga
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Abstract

The Kondo lattice model (KLM) is a typical model describing heavy fermion systems. In this paper, we consider the interaction of phonons with the system described by the one-electron KLM. Magnetic properties of the ground state of this model are revealed in a rigorous form. Furthermore, we derive the effective Hamiltonian in the strong coupling limit ($J\to \infty$) for the strength of the spin-exchange interaction $J$; we examine the magnetic properties of the ground state of the effective Hamiltonian and prove that the Aizenman--Lieb theorem concerning the magnetization holds for the effective Hamiltonian at finite temperatures. Generalizing the obtained results, we clarify a mechanism for the stability of magnetic properties of the ground state in the one-electron KLM system.

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Tadahiro Miyao, Kazuhiro Nishimata, Hayato Tominaga. 2022-04-19. Rigorous analysis of the effects of electron-phonon interactions on magnetic properties in the one-electron Kondo lattice model. https://arxiv.org/abs/2204.08675

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