Kondo-Ising and Tight-Binding Models for TmB4

Abstract

In $Tm{B}_4$, localized electrons with a large magnetic moment interact with metallic electrons in boron-derived bands. We examine the nature of $Tm{B}_4$ using full-relativistic ab-initio density functional theory calculations, approximate tight-binding Hamiltonian results, and the development of an effective Kondo-Ising model for this system. Features of the Fermi surface relating to the anisotropic conduction of charge are discussed. The observed magnetic moment $\sim 6{\mu }_B$ is argued to require a subtle crystal field effect in metallic systems, involving a flipped sign of the effective charges surrounding a Tm ion. The role of on-site quantum dynamics in the resulting Kondo-Ising type "impurity" model are highlighted. From this model, elimination of the conduction electrons will lead to spin-spin (RKKY-type) interaction of Ising character required to understand the observed fractional magnetization plateaus in $Tm{B}_4$.

References in corpus (6)

• Anisotropy and Magnetism in the LSDA+U Method
• Fractional magnetization plateaus and magnetic order in the Shastry Sutherland magnet TmB4
• Layered Kondo lattice model for quantum critical beta-YbAlB4
• Electronic Transport on the Shastry-Sutherland Lattice in Ising-type Rare Earth Tetraborides
• Hysteretic magnetoresistance and unconventional anomalous Hall effect in the frustrated magnet TmB_4
• Origin of modulated phases and magnetic hysteresis in TmB_4

Cited by in corpus (5)

• Quadratic to linear magnetoresistance tuning in TmB4
• Skyrmion-driven topological Hall effect in a Shastry-Sutherland magnet
• Phase Diagram of the Shastry-Sutherland Kondo Lattice Model with Classical Localized Spins: A Variational Calculation Study
• Magnon Bose-Einstein Condensation and Superconductivity in a Frustrated Kondo Lattice
• Bosonic Peierls state emerging from the one-dimensional Ising-Kondo interaction