Digital modulation of the nickel valence state in a cuprate-nickelate heterostructure

Abstract

Layer-by-layer oxide molecular beam epitaxy has been used to synthesize cuprate-nickelate multilayer structures of composition (La${}_2$CuO${}_4$)${}_m$/LaO/(LaNiO${}_3$)${}_n$. In a combined experimental and theoretical study, we show that these structures allow a clean separation of dopant and doped layers. Specifically, the LaO layer separating cuprate and nickelate blocks provides an additional charge that, according to density functional theory calculations, is predominantly accommodated in the interfacial nickelate layers. This is reflected in an elongation of bond distances and changes in valence state, as observed by scanning transmission electron microscopy and x-ray absorption spectroscopy. Moreover, the predicted charge disproportionation in the nickelate interface layers leads to a thickness-dependent metal-to-insulator transition for $n=2$, as observed in electrical transport measurements. The results exemplify the perspectives of charge transfer in metal-oxide multilayers to induce doping without introducing chemical and structural disorder.

References in corpus (23)

• Quantum ESPRESSO: a modular and open-source software project for quantum simulations of materials
• A linear response approach to the calculation of the effective interaction parameters in the LDA+U method
• Complexity in Strongly Correlated Electronic Systems
• Why Some Interfaces Cannot be Sharp
• Orbital order and possible superconductivity in LaNiO3/LaMO3 superlattices
• Quantifying octahedral rotations in strained perovskite oxide films
• Site-selective Mott transition in rare earth nickelates
• Physics of ultrathin films and heterostructures of rare earth nickelates
• Charge disproportionation without charge transfer in the rare-earth nickelates as a possible mechanism for the metal-insulator transition
• Mimicking cuprates: large orbital polarization in a metallic square-planar nickelate
• Structurally Triggered Metal-Insulator Transition in Rare-Earth Nickelates
• Reconciling the ionic and covalent pictures in rare-earth nickelates
• Orbital control in strained ultra-thin LaNiO${}_3$/LaAlO${}_3$ superlattices
• Charge transfer driven emergent phenomena in oxide heterostructures
• Confinement-induced metal-to-insulator transition in strained LaNiO${}_3$/LaAlO${}_3$ superlattices
• Design of $n$- and $p$-type oxide thermoelectrics in LaNiO${}_3$/SrTiO${}_3(001)$ superlattices exploiting interface polarity
• Measurement Error in Atomic-Scale STEM-EDS Mapping of a Model Oxide Interface
• Formal Valence, $d$ Occupation, and Charge-Order Transitions
• Bandwidth-disorder phase diagram of half doped layered manganites
• Comparative study of LaNiO${}_3$/LaAlO${}_3$ heterostructures grown by pulsed laser deposition and oxide molecular beam epitaxy
• Orbital engineering in nickelate heterostructures driven by anisotropic oxygen hybridization rather than orbital energy levels
• Charge and orbital order in RNiO3 (R=Nd,Y) by LSDA+U method
• Effect of charge doping on the electronic structure, orbital polarization, and structural distortion in nickelate superlattice

Cited by in corpus (15)

• Unconventional crystal structure of the high-pressure superconductor La${}_3$Ni${}_2$O${}_7$
• Structural transitions, octahedral rotations, and electronic properties of $A_3$Ni${}_2$O${}_7$ rare-earth nickelates under high pressure
• Fundamental difference in the electronic reconstruction of infinite-layer vs. perovskite neodymium nickelate films on SrTiO${}_3$(001)
• Confinement- and strain-induced enhancement of thermoelectric properties in LaNiO${}_3$/LaAlO${}_3(001)$ superlattices
• Correlated interface electron gas in infinite-layer nickelate versus cuprate films on SrTiO${}_3$(001)
• Inducing $n$- and $p$-type thermoelectricity in oxide superlattices by strain tuning of orbital-selective transport resonances
• Competition of defect ordering and site disproportionation in strained LaCoO${}_3$ on SrTiO${}_3$(001)
• Oxygen vacancy formation and electronic reconstruction in strained LaNiO${}_3$ and LaNiO${}_3$/LaAlO${}_3$ superlattices
• Tunable perpendicular exchange bias in oxide heterostructures
• Nature of the magnetic coupling in infinite-layer nickelates versus cuprates
• PERSPECTIVE: Emergent phases in rare earth nickelate heterostructures
• Coupling of electronic and structural degrees of freedom in vanadate superlattices
• Rashba spin-orbit coupling in infinite-layer nickelate films on SrTiO3(001) and KTaO3(001)
• Fermi surface reconstruction and enhanced spin fluctuations in strained La${}_3$Ni${}_2$O${}_7$ on LaAlO${}_3$(001) and SrTiO${}_3$(001)
• Electronic reconstruction and interface engineering of emergent spin fluctuations in compressively strained La${}_3$Ni${}_2$O${}_7$ on SrLaAlO${}_4$(001)