2D Surface Phase Diagram of a Multicomponent Perovskite Oxide: La$_{0.8}$Sr$_{0.2}$MnO$_3$(110)

Abstract

The many surface reconstructions of (110)-oriented lanthanum-strontium manganite (La0.8Sr0.2MnO3, LSMO) were followed as a function of the oxygen chemical potential (µ O ) and the surface cation composition. Decreasing µ O causes Mn to migrate across the surface, enforcing phase separation into A-site-rich areas and a variety of composition-related, structurally diverse B-site-rich reconstructions. The composition of these phase-separated structures was quantified with scanning tunneling microscopy (STM), and these results were used to build a 2D phase diagram of the LSMO(110) equilibrium surface structures.

Exotic Long-Range Surface Reconstruction on La0.7Sr0.3MnO3 Thin Films

“…To broaden the breadth of LSMO studies, we chose a (001) pc NdGaO 3 template for inducing a slight compressive strain (0.52%), to complement the traditional substrate of choice, i.e., SrTiO 3 with a slight tensile strain (0.77%), which has been the subject of many works. 46 The surface is characterized by low-energy electron diffraction (LEED) accompanied by density functional theory (DFT) computation and electron spectroscopy modeling. By employing a universal in situ framework with scanning tunneling microscopy (STM) in conjunction with angle-dependent X-ray photoelectron spectroscopy (XPS), we identify the surface morphology and elemental concentrations at the surface, which is in agreement with previous LSMO surface studies.…”