Electronic structure and magnetic properties of the effective spin J eff = 1 2 two-dimensional triangular lattice K 3 Yb ( VO 4 ) 2
Résumé
We report the structural, magnetic, specific heat, and electronic structure studies of the material K3Yb(VO4)2, which has two-dimensional triangular layers constituted by rare-earth magnetic Yb 3+ ions. Magnetic susceptibility data shows the absence of magnetic long-range order down to 0.5 K. No bifurcation is observed between zero-field-cooled and field-cooled magnetic susceptibility data ruling out the possibility of spin-glassiness down to 0.5 K. From the fit to magnetic susceptibility data with Curie-Weiss law in the low-temperature region, the observed Curie-Weiss temperature (θ CW) is about −1 K, implying an antiferromagnetic coupling between the Yb 3+ ions. Magnetic field-dependent specific heat fits well with two-level Schottky behavior. The analysis of magnetization and specific heat data confirms that the Yb 3+ ion hosts the effective spin-1/2 state. To provide a microscopic understanding of the ground state nature of the titled material, we carried out state-of-the-art firstprinciple calculations based on density functional theory + Hubbard U (DFT+U) and density functional theory + dynamical mean-field theory (DFT+DMFT) approaches. Our calculations reveal that the system belongs to the novel class of spin-orbit driven Mott Hubbard insulators and possesses large in-plane magnetocrystalline anisotropy.
Domaines
Physique [physics]
Origine : Fichiers produits par l'(les) auteur(s)