Atomic Lattice and Electronic Structure of Superconducting Nickelate Thin Films*

The stabilization of superconducting infinite-layer nickelate thin films [1,2] presents a long-awaited platform for experimental comparison to the analogous cuprate superconductors and exploration of the underlying physical mechanisms. Unlike the bulk-synthesized cuprates, however, the thin film geometry of the superconducting nickelates motivates both structural and electronic characterization with high real-space resolution. Here, we harness atomic-scale scanning transmission electron microscopy (STEM) and localized electron energy loss spectroscopy (EELS) to explore both the lattice and electronic structure across a wide series of nickelate thin films. Combining high spatial and energy resolution, we spectroscopically reveal key electronic differences with the cuprate superconductors [3]. We also explore the role of the substrate with quantitative structural analysis.

1. Li, D. et al. Nature 572, 624 (2019).
2. Osada, M. et al. Nano Lett. 20, 5735 (2020).
3. Goodge, B. H. et al. arXiv:2005.02847 (2020).