Strain-Induced Gradient Distribution of Dopants at a Perovskite Interface.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 39905675.
- Also identified by DOI 10.1021/acs.nanolett.4c05137.
- 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
Interfaces often trap dopants for segregation and significantly affect the material properties. Because interfacial segregation sometimes is harmful, revealing mechanisms to reduce the extent of interface segregation is important. Here we investigate the Sr segregation behavior in LaTiO<sub>3.5</sub>/LaTiO<sub>3</sub>/LaTiO<sub>3.5</sub> sandwich heterostructures by transmission electron microscopy and first-principles calculations. This reveals that Sr atoms prefer to segregate in LaTiO<sub>3</sub> by replacing La atoms rather than LaTiO<sub>3.5</sub>. The Sr concentration in LaTiO<sub>3</sub> increases with the thickness of the LaTiO<sub>3</sub> layer and exhibits an obvious gradient distribution. First-principles calculations suggest that the electrostatic potential drives Sr atoms from LaTiO<sub>3.5</sub> to LaTiO<sub>3</sub>. The low Sr concentration at the interfaces is induced by an interfacial strain. The sandwiched LaTiO<sub>3</sub> layer changes from n-type conduction to insulation and to p-type conduction with an increase in Sr concentration. The finding that the strain concentration sometimes reduces the extent of interface segregation provides a new approach for the design and regulation of material interfaces.