Surface triggered stabilization of metastable charge-ordered phase in SrTiO<sub>3</sub>.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 38332134.
- Also identified by DOI 10.1038/s41467-024-45342-8 and PMC identifier 10853244.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Charge ordering (CO), characterized by a periodic modulation of electron density and lattice distortion, has been a fundamental topic in condensed matter physics, serving as a potential platform for inducing novel functional properties. The charge-ordered phase is known to occur in a doped system with high d-electron occupancy, rather than low occupancy. Here, we report the realization of the charge-ordered phase in electron-doped (100) SrTiO<sub>3</sub> epitaxial thin films that have the lowest d-electron occupancy i.e., d<sup>1</sup>-d<sup>0</sup>. Theoretical calculation predicts the presence of a metastable CO state in the bulk state of electron-doped SrTiO<sub>3</sub>. Atomic scale analysis reveals that (100) surface distortion favors electron-lattice coupling for the charge-ordered state, and triggering the stabilization of the CO phase from a correlated metal state. This stabilization extends up to six unit cells from the top surface to the interior. Our approach offers an insight into the means of stabilizing a new phase of matter, extending CO phase to the lowest electron occupancy and encompassing a wide range of 3d transition metal oxides.