Layered nickelates have been studied extensively over the last three decades due to their structural similarities to the high-$T_c$ superconducting cuprates. Using reactive oxide molecular beam epitaxy (MBE), we synthesize ${\mathrm{Nd}}_{2-x}{\mathrm{Sr}}_x{\mathrm{NiO}}_4$ thin films for $x=0-1.4$ to probe the properties and electronic structure as a function of hole doping. The samples with lower doping show semiconducting behavior across the temperatures probed with an onset of metallic conductivity at $x=1.4$. We also present polarization-dependent O $K$ and Ni $L_{2,3}$ x-ray absorption spectra to track the evolution of the oxygen-nickel hybridization, distribution of holes between O $2p$ and Ni $3d$ states and the nickel oxidation state across the series. Angle-resolved photoemission spectroscopy (ARPES) measurements reveal a Fermi surface that comprises a cupratelike hole pocket of $d_{x^2-y^2}$ character with an additional electron pocket of $d_{3z^2-r^2}$ character at $\mathrm{\Gamma }$. The emergence of a quasiparticle peak at the Fermi vector for $x=1.4$ corroborates the insulator-to-metal transition at $x\sim 1$. Finally, observe a fully two-dimensional Fermi surface with no momentum-dependent pseudogap, in contrast to measurements of the related bulk compound, ${\mathrm{Eu}}_{0.9}{\mathrm{Sr}}_{1.1}{\mathrm{NiO}}_4$.

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• Composition
• Crystal growth
• Crystal structure
• Doping effects
• Electrical properties
• Electronic structure
• Fermi surface
• Hall effect
• Jahn-Teller effect
• Metal-insulator transition
• Valence
• Strongly correlated systems
• Thin films
• Angle-resolved photoemission spectroscopy
• Molecular beam epitaxy
• X-ray absorption spectroscopy