Dimensionality-tuned electronic structure of nickelate superlattices explored by soft-x-ray angle resolved photoelectron spectroscopy

Abstract

The electronic and magnetic properties of epitaxial LaNiO3/LaAlO3 superlattices can be tuned by layer thickness and substrate-induced strain. Here, we report on direct measurements of the k-space-resolved electronic structure of buried nickelate layers in superlattices under compressive strain by soft x-ray photoemission. After disentangling strong extrinsic contributions to the angle-dependent signal caused by photoelectron diffraction, we are able to extract Fermi surface information from our data. We find that with decreasing LaNiO3 thickness down to two unit cells (2 uc) quasiparticle coherence becomes strongly reduced, in accord with the dimension-induced metal-to-insulator transition seen in transport measurements. Nonetheless, on top of a strongly incoherent background a residual Fermi surface can be identified in the 2 uc superlattice whose nesting properties are consistent with the spin-density wave (SDW) instability recently reported. The overall behavior of the Ni 3d spectra and the absence of a complete gap opening indicate that the SDW phase is dominated by strong order parameter fluctuations.

11 pages, 7 figures

References in corpus (8)

• Orbital order and possible superconductivity in LaNiO3/LaMO3 superlattices
• Tunable Charge and Spin Order in PrNiO${}_3$ Thin Films and Superlattices
• Fermi surfaces, electron-hole asymmetry and correlation kink in a three-dimensional Fermi liquid LaNiO${}_3$
• High-energy photoemission on Fe3O4: Small polaron physics and the Verwey transition
• Chemical control of orbital polarization in artificially structured transition-metal oxides: La2NiXO6 (X=B, Al, Ga, In) from first principles
• Confinement-induced metal-to-insulator transition in strained LaNiO${}_3$/LaAlO${}_3$ superlattices
• Latent Instabilities in Metallic LaNiO3 Films by Strain Control of Fermi-Surface Topology
• Strain-controlled band engineering and self-doping in ultrathin LaNiO${}_3$ films

Cited by in corpus (6)

• Physics of ultrathin films and heterostructures of rare earth nickelates
• Angle-resolved photoemission spectroscopy
• Electronic structure of superconducting nickelates probed by resonant photoemission spectroscopy
• Comparative study of LaNiO${}_3$/LaAlO${}_3$ heterostructures grown by pulsed laser deposition and oxide molecular beam epitaxy
• Hybridization-switching induced Mott transition in ABO${}_3$ perovskites
• Electronic structure of buried LaNiO3 layers in (111)-oriented LaNiO3/LaMnO3 superlattices probed by soft x-ray ARPES