Polaronic and Mott insulating phase of layered magnetic vanadium trihalide VCl3

Abstract

Two-dimensional (2D) van der Waals (vdW) magnetic $3d$-transition metal trihalides are a new class of functional materials showing exotic physical properties useful for spintronic and memory storage applications. In this article, we report the synthesis and electromagnetic characterization of single-crystalline vanadium trichloride, VCl${}_3$, a novel 2D layered vdW Mott insulator, which has a rhombohedral structure (R$\overline{3}$, No. 148) at room temperature. VCl${}_3$ undergoes a structural phase transition at 103 K and a subsequent antiferromagnetic transition at 21.8 K. Combining core levels and valence bands x-ray photoemission spectroscopy (XPS) with first-principles density functional theory (DFT) calculations, we demonstrate the Mott Hubbard insulating nature of VCl${}_3$ and the existence of electron small 2D magnetic polarons localized on V atom sites by V-Cl bond relaxation. The polarons strongly affect the electromagnetic properties of VCl${}_3$ promoting the occupation of dispersion-less spin-polarized V-3d $a_{1g}$ states and band inversion with $e_g^{{}^{\prime }}$ states. Within the polaronic scenario, it is possible to reconcile different experimental evidences on vanadium trihalides, suggesting that also VI${}_3$ hosts polarons. Our results highlight the complex physical behavior of this class of crystals determined by charge trapping, lattice distortions, correlation effects, mixed valence states, and magnetic states.

References in corpus (12)

• Two dimensional magnets: Forgotten history and recent progress towards spintronic applications
• VI3 - a new layered ferromagnetic semiconductor
• Intrinsic magnetism in monolayer transition metal trihalides: a comparative study
• Polarons in two-dimensional atomic crystals
• Magnetic polaron and antiferro-ferromagnetic transition in doped bilayer CrI${}_3$
• Large orbital magnetic moment in VI3
• Trigonal Symmetry Breaking and its Electronic Effects in Two-Dimensional Dihalides and Trihalides
• Crystallographic and magnetic structures of the VI${}_3$ and LiVI${}_3$ van der Waals compounds
• Self-selecting vapor growth of transition metal halide single crystals
• Interplay of spin magnetism, orbital magnetism, and atomic structure in layered van der Waals ferromagnet VI${}_3$
• Crystal structure evolution in the van der Waals transition metal trihalides
• Polarization dependent photoemission as a probe of the magnetic ground state in the layered ferromagnet VI3

Cited by in corpus (6)

• Evidence of Ferroelectricity in an Antiferromagnetic Vanadium Trichloride Monolayer
• Multiferroic nematic d-wave altermagnetism driven by orbital-order on the honeycomb lattice
• Symmetry breaking in vanadium trihalides
• Multicomponent magneto-orbital order and magneto-orbitons in monolayer VCl3
• Tailoring Robust Quantum Anomalous Hall Effect via Entropy-Engineering
• Valence Modifications in Hygroscopic VI3 Degraded Crystals via Soft X-Ray Synchrotron Radiation