VO: A strongly correlated metal close to a Mott-Hubbard transition

Abstract

Here, we present experimental and computational evidences to support that rocksalt cubic VO is a strongly correlated metal with non-Fermi-liquid thermodynamics and an unusually strong spin-lattice coupling. An unexpected change of sign of metallic thermopower with composition is tentatively ascribed to the presence of a pseudogap in the density of states. These properties are discussed as signatures of the proximity to a magnetic quantum phase transition. The results are summarized in an electronic phase diagram for the 3d monoxides, which resembles that of other strongly correlated systems. The structural and electronic simplicity of 3d monoxides makes them ideal candidates to progress in the understanding of highly correlated electron systems.

Tunable resistivity exponents in the metallic phase of epitaxial nickelates

“…Therefore, the scaling exponent of the powerlaw term of the resistivity as a function of temperature (n) is often used to infer the type of interactions ruling the metal state. In materials with strong electron-electron interactions and undergoing ordering phenomena, other exponents (n ≠ 1, 2) are usually observed, being the physics behind this so-called 'Non-Fermi liquid' (NFL) behaviour [11][12][13] , a subject of active discussion [14][15][16][17] .…”

Electronic Structure of the VO Film Grown on Ag(100): Resonant Photoelectron Spectroscopy Study

“…The band is ascribed to the partially filled conduction band mostly composed of V 3d components. Theoretical studies have predicted that the V 3d band in the occupied region is mostly composed of the t 2g states [20,21]. It is deduced from the results of resonant PES measurements that the valence band of the VO film mostly composed of O 2p components appears at 4-10 eV overlapping with the substrate Ag 4d band that is attenuated by the inelastic scattering of Ag 4d photoelectrons in the VO overlayer, as will be discussed later.…”

“…The electronic structures of 3d transition metal monoxides have attracted attention because these are promising candidates for the model systems to understand the properties of highly correlated electron systems owing to their structural and electronic simplicity. It has been revealed that the monoxides of Mn, Fe, Co, and Ni (group 7, 8, 9, and 10 transition metals, respectively) are antiferromagnetic insulators while TiO (group 4 transition metal monoxide) is a Fermi-liquid metal [21]. VO (group 5 transition metal monoxide) locates in the midst of these two groups, and the electronic structure has attracted attention.…”

“…The metallic electronic structure has been predicted by Yamazaki and Fujiwara using GW calculations [20], while VO has been predicted to be an antiferromagnetic insulator by Mackrodt et al using hybrid DFT calculations [34]. Rivadulla et al made the study by the use of magnetic susceptibility and thermoelectric power measurements together with DFT calculations, and predicted that VO is a strongly correlated metal whose electronic structure is characterized by the existence of a pseudo gap around E F [21]. In this study, the PES studies clearly shows that, at least in the case of the ultrathin VO(100) film formed in this study, the electronic structure is metallic without a pseudo gap around E F at least above 4.86 K.…”

Thermodynamic, lattice dynamical, and elastic properties of iron‐vanadium oxides from experiments and first principles

“…However, the errors of vanadium oxides are relatively large because they fitted the energy adjustment of V element with all binary vanadium oxides. VO is a strongly correlated metal exhibiting different character compared with other vanadium oxide semiconductors. Thus, we modify the energy adjustment of V element to be 1.564 eV without considering VO.…”