Strain Dependent Electronic Structure and Band Offset Tuning at Heterointerfaces of ASnO₃ (A=Ca, Sr, and Ba) and SrTiO₃.

ABSTRACT: The valence band (VB) electronic structure and VB alignments at heterointerfaces of strained epitaxial stannate ASnO₃ (A=Ca, Sr, and Ba) thin films are characterized using in situ X-ray and ultraviolet photoelectron spectroscopies, with band gaps evaluated using spectroscopic ellipsometry. Scanning transmission electron microscopy with geometric phase analysis is used to resolve strain at atomic resolution. The VB electronic structure is strain state dependent in a manner that correlated with a directional change in Sn-O bond lengths with strain. However, VB offsets are found not to vary significantly with strain, which resulted in ascribing most of the difference in band alignment, due to a change in the band gaps with strain, to the conduction band edge. Our results reveal sig

SUBMITTER: Baniecki JD 

PROVIDER: S-EPMC5307316 | biostudies-literature | 2017 Feb

REPOSITORIES: biostudies-literature