Probing electronic dead layers in homoepitaxial n-SrTiO3(001) films
Abstract
We combine state-of-the-art oxide epitaxial growth by hybrid molecular beam epitaxy with transport, x-ray photoemission, and surface diffraction, along with classical and first-principles quantum mechanical modeling to investigate the nuances of insulating layer formation in otherwise high-mobility homoepitaxial n-SrTiO3(001) films. Our analysis points to charge immobilization at the buried n-SrTiO3/undoped SrTiO3(001) interface as well as within the surface contamination layer resulting from air exposure as the drivers of electronic dead-layer formation. As Fermi level equilibration occurs at the surface and the buried interface, charge trapping reduces the sheet carrier density (n2D) and renders the n-STO film insulating if n2D falls below the critical value for the metal-to-insulator transition.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Jul 01, 2022
- Source ID
- 10.1063/5.0098500
Entities
People
- Bharat Jalan
- Dooyong Lee
- Huibin Zhou
- Judith Gabel
- L. W. Wangoh
- P. V. Sushko
- Scott A. Chambers
- T.-l. Lee
- Tristan K. Truttmann
- W. Samarakoon
- Yi Huang
- Zhengyu Yang
Organizations
- Air Force Office of Scientific Research
- Argonne National Laboratory
- Diamond Light Source
- International Business Machines Corporation (Armonk, NY)
- National Science Foundation
- Oregon State University
- Pacific Northwest National Laboratory
- United States Department of Energy
- University of Minnesota