Doping evolution and polar surface reconstruction of the infinite-layer cuprate Sr${}_{1-x}$La${}_x$CuO${}_2$

Abstract

We use angle-resolved photoemission spectroscopy to study the doping evolution of infinite-layer Sr${}_{1-x}$La${}_x$CuO${}_2$ thin films grown by molecular-beam epitaxy. At low doping, the material exhibits a dispersive lower Hubbard band typical of the superconducting cuprate parent compounds. As carriers are added to the system, a continuous evolution from charge-transfer insulator to superconductor is observed, with the initial lower Hubbard band pinned well below the Fermi level and the development of a coherent low-energy band with electron doping. This two-component spectral function emphasizes the important role that strong local correlations play even at relatively high doping levels. Electron diffraction probes reveal a $p(2\times 2)$ surface reconstruction of the material at low doping levels. Using a number of simple assumptions, we develop a model of this reconstruction based on the polar nature of the infinite-layer structure. Finally, we provide evidence for a thickness-controlled transition in ultrathin films of SrCuO${}_2$ grown on nonpolar SrTiO${}_3$, highlighting the diverse structural changes that can occur in polar complex oxide thin films.

References in corpus (7)

• A universal high energy anomaly in angle resolved photoemission spectra of high temperature superconductors - possible evidence of spinon and holon branches
• "Waterfalls" phenomenon in superconducting cuprates
• "Waterfalls" in cuprates
• Effect of strong correlations on the high energy anomaly in hole- and electron-doped high-Tc superconductors
• Nodeless superconductivity arising from strong (pi,pi) antiferromagnetism in the infinite-layer electron-doped cuprate Sr1-xLaxCuO2
• Prediction of thickness limits of ideal polar ultrathin films
• Antiferromagnetism-superconductivity competition in electron-doped cuprates triggered by oxygen reduction

Cited by in corpus (10)

• Direct visualization of ambipolar Mott transition in cuprate CuO2 planes
• Advances in Complex Oxide Quantum Materials Through New Approaches to Molecular Beam Epitaxy
• Atomic Visualization of Copper Oxide Structure in Infinite-Layer Cuprate SrCuO2
• ARPES Detection of Superconducting Gap Sign in Unconventional Superconductors
• Anisotropic dressing of electrons in electron-doped cuprate superconductors
• Magnon interactions in a moderately correlated Mott insulator
• Molecular beam epitaxy growth and surface structure of Sr1-xNdxCuO2 cuprate films
• Universal Chemical Formula Dependence of $Ab$ $Initio$ Low-Energy Effective Hamiltonian in Single-Layer Carrier Doped Cuprate Superconductors -- Study by Hierarchical Dependence Extraction Algorithm
• Magnetic phases of electron-doped infinite-layer Sr${}_{1-x}$La${}_x$CuO${}_2$ from first-principles density functional calculations
• An emergent quasi-2D metallic state derived from the Mott insulator framework