Electronic Localization in CaVO3 Films via Bandwidth Control

Abstract

Understanding and controlling the electronic structure of thin layers of quantum materials is a crucial first step towards designing heterostructures where new phases and phenomena, including the metal-insulator transition (MIT), emerge. Here, we demonstrate control of the MIT via tuning electronic bandwidth and local site environment through selection of the number of atomic layers deposited. We take CaVO3, a correlated metal in its bulk form that has only a single electron in its V4+ 3d manifold, as a representative example. We find that thick films and ultrathin films (6 unit cells, uc, and below) are metallic and insulating, respectively, while a 10 uc CaVO3 film exhibits a clear thermal MIT. Our combined X-ray absorption spectroscopy and resonant inelastic x-ray scattering (RIXS) study reveals that the thickness-induced MIT is triggered by electronic bandwidth reduction and local moment formation from V3+ ions, that are both a consequence of the thickness confinement. The thermal MIT in our 10 uc CaVO3 film exhibits similar changes in the RIXS response to that of the thickness-induced MIT in terms of reduction of bandwidth and V 3d - O 2p hybridization.

arXiv comment27 pages, 6 figures

References in corpus (15)

• Mott transition and suppression of orbital fluctuations in orthorhombic 3$d^1$ perovskites
• Metal-insulator transition in ultrathin LaNiO3 films
• Ground state oxygen holes and the metal-insulator transition in the negative charge transfer rare-earth nickelates
• Emergent properties hidden in plane view: Strong electronic correlations at oxide interfaces
• Band-width control in a perovskite-type 3d^1 correlated metal Ca_{1-x}Sr_xVO_3. I. Evolution of the electronic properties and effective mass
• Electronics with correlated oxides: SrVO${}_3$/SrTiO${}_3$ as a Mott transistor
• Insulating phase at low temperature in ultrathin La0.8Sr0.2MnO3 films
• Tuning the metal-insulator transition in NdNiO3 heterostructures via Fermi surface instability and spin-fluctuations
• Charge-order-induced ferroelectricity in LaVO${}_3$/SrVO${}_3$ superlattices
• Metal-insulator transition induced in SrTi_{1-x}V_xO_3 thin films
• Orbital superexchange and crystal field simultaneously at play in YVO3: resonant inelastic x-ray scattering at the V L edge and the O K edge
• Evidence for core-hole-mediated inelastic x-ray scattering from metallic Fe${}_{1.087}$Te
• Metal-insulator transition in CaVO${}_3$ thin films: interplay between epitaxial strain, dimensional confinement, and surface effects
• Resonant soft x-ray emission as a bulk probe of correlated electron behavior in metallic Sr${}_x$Ca${}_{1-x}$VO${}_3$
• Metal-Insulator Transitions and non-Fermi Liquid Behaviors in 5d Perovskite Iridates

Cited by in corpus (8)

• On the effect of charge self-consistency in DFT+DMFT calculations for complex transition metal oxides
• Orbital dynamics during an ultrafast insulator to metal transition
• Description of resonant inelastic x-ray scattering in correlated metals
• Anisotropy of electronic correlations: On the applicability of local theories to layered materials
• Isostructural Metal-Insulator Transition Driven by Dimensional-Crossover in SrIrO3 Heterostructures
• Structural and transport properties of La${}_{1-x}$Sr${}_x$Co${}_{1-y}$Nb${}_y$O${}_3$ thin films
• Multilayer engineering of CaVO${}_3$ thin films with SrTiO${}_3$ and LaAlO${}_3$ from DFT+DMFT
• Dynamical screening in SrVO${}_3$: Inelastic x-ray scattering experiments and ab initio calculations