Phase evolution of the two-dimensional Kondo lattice model near half-filling

Abstract

Within a mean-field approximation, the ground state and finite temperature phase diagrams of the two-dimensional Kondo lattice model have been carefully studied as functions of the Kondo coupling $J$ and the conduction electron concentration $n_c$. In addition to the conventional hybridization between local moments and itinerant electrons, a staggered hybridization is proposed to characterize the interplay between the antiferromagnetism and the Kondo screening effect. As a result, a heavy fermion antiferromagnetic phase is obtained and separated from the pure antiferromagnetic ordered phase by a first-order Lifshitz phase transition, while a continuous phase transition exists between the heavy fermion antiferromagnetic phase and the Kondo paramagnetic phase. We have developed a efficient theory to calculate these phase boundaries. As $n_c$ decreases from the half-filling, the region of the heavy fermion antiferromagnetic phase shrinks and finally disappears at a critical point $n_c^{\ast }=0.8228$, leaving a first-order critical line between the pure antiferromagnetic phase and the Kondo paramagnetic phase for $n_c<n_c^{\ast }$. At half-filling limit, a finite temperature phase diagram is also determined on the Kondo coupling and temperature ($J$-$T$) plane. Notably, as the temperature is increased, the region of the heavy fermion antiferromagnetic phase is reduced continuously, and finally converges to a single point, together with the pure antiferromagnetic phase and the Kondo paramagnetic phase. The phase diagrams with such triple point may account for the observed phase transitions in related heavy fermion materials.

9 pages, 9 figures

References in corpus (9)

• Fermi-liquid instabilities at magnetic quantum phase transitions
• Heavy Fermions and Quantum Phase Transitions
• Fermi Surface Reconstruction without Breakdown of Kondo Screening at Quantum Critical Point
• Fermi surface topology of the two-dimensional Kondo lattice model: a dynamical cluster approximation approach
• Fermi Surface Reconstruction in CeRh${}_{1-x}$Co${}_x$In${}_5$
• Evolution of the Fermi Surface across a Magnetic Order-Disorder Transition in the Two-Dimensional Kondo Lattice Model: A Dynamical Cluster Approach
• Fermi surface of CeIn3 above the Neel critical field
• Weak ferromagnetism with the Kondo screening effect in the Kondo lattice systems
• Heavy antiferromagnetic phases in Kondo lattices

Cited by in corpus (8)

• Doping-dependent character and possible magnetic ordering of NdNiO${}_2$
• Toward a New Microscopic Framework for Kondo Lattice Materials
• Spiral magnetic phases on the Kondo Lattice Model: A Hartree-Fock approach
• Altermagnetism in Heavy Fermion Systems: Mean-Field study on Kondo Lattice
• Phase evolution of Ce-based heavy-fermion superconductors under compression: a combined first-principle and effective-model study
• Heavy quasiparticle bands in the underscreened quasiquartet Kondo lattice
• Degenerate orbital effect in a three orbital periodic Anderson model
• Optical and magnetic excitations in the underscreened quasi-quartet Kondo lattice