Defect and Strain Engineering Coenhanced Nanoscale Ferroelectricity in SrTiO<sub>3</sub> Thin Films.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 40139942.
- Also identified by DOI 10.1021/acsnano.5c03518.
- No licence information is recorded for this record.
- Because redistribution is not established, this page shows the abstract only. Follow the links below for the full text.
Abstract
Tensile biaxial strain has been demonstrated to induce in-plane ferroelectricity in SrTiO<sub>3</sub> thin films at room temperature. However, out-of-plane ferroelectricity is more favorable for electronic device applications. Here, we report the achievement of room-temperature out-of-plane ferroelectric SrTiO<sub>3</sub> thin films with giant tetragonality (<i>c</i>/<i>a</i> ∼ 1.061) and an ultrahigh ferroelectric stablity temperature (>1000 K) through epitaxial strain and defect engineering. Optical second-harmonic generation (SHG) proves that the enhancement of tetragonality enables improved ferroelectricity. Moreover, a combination of scanning transmission electron microscopy (STEM) and X-ray absorption near-edge spectroscopy (XANES) reveals the origin of enhanced tetragonality and strong ferroelectricity in defect- and strain-codriven supertetragonal SrTiO<sub>3</sub> thin films. Our findings present an approach to material design that can be extended to other material systems for the enhancement of ferroelectricity and the observation of emergent phenomena.