Braiding lateral morphotropic grain boundary in homogeneitic oxides

TL;DR

This paper demonstrates a scalable method to create atomically sharp, morphotropic grain boundaries in homogeneitic oxides, enabling lateral modulation of electronic and magnetic properties for advanced functional applications.

Contribution

It introduces a novel fabrication approach for seamless, controlled grain boundaries in oxide structures using epitaxial growth on substrates and membranes.

Findings

Seamless, atomically sharp grain boundaries achieved in cobaltite oxides.

Lateral electronic and magnetic modulation demonstrated across grain boundaries.

Potential applications in neuromorphic systems, batteries, and catalysis.

Abstract

Interfaces formed by correlated oxides offer a critical avenue for discovering emergent phenomena and quantum states. However, the fabrication of oxide interfaces with variable crystallographic orientations and strain states integrated along a film plane is extremely challenge by conventional layer-by-layer stacking or self-assembling. Here, we report the creation of morphotropic grain boundaries (GBs) in laterally interconnected cobaltite homostructures. Single-crystalline substrates and suspended ultrathin freestanding membranes provide independent templates for coherent epitaxy and constraint on the growth orientation, resulting in seamless and atomically sharp GBs. Electronic states and magnetic behavior in hybrid structures are laterally modulated and isolated by GBs, enabling artificially engineered functionalities in the planar matrix. Our work offers a simple and scalable method for fabricating unprecedented innovative interfaces through controlled synthesis routes as well as provides a platform for exploring potential applications in neuromorphics, solid state batteries, and catalysis.