Abstract
Orthorhombic is a typical spin-orbit-coupled correlated metal that shows diversified physical properties under external stimuli. Here the nonlinear Hall effect and weakly temperature-dependent resistance are observed in a film epitaxially grown on a substrate. It infers that orthorhombic is a semimetal oxide. However, a linear Hall effect and insensitive-temperature-dependent resistance are observed in films grown on (LSAT) substrates, suggesting a tunable semimetallic state due to a band structure change in films under different compressive strains. The mechanism of this evolution is explored in detail through a strain-state analysis by reciprocal space mapping and electron diffraction, carrier density and mobility calculations, as well as electronic band structure evolution under compressive strain (predicted by a tight-binding approximation). It might suggest that the strain-induced band shift leads to semimetallic tuning in the film grown on to LSAT substrates. Our findings illustrate the tunability of properties and pave the way to induce different physical states in , such as the proposed topological insulator state in heterostructures.
- Received 18 June 2014
- Revised 8 October 2014
DOI:https://doi.org/10.1103/PhysRevB.91.035110
©2015 American Physical Society