Electronic reconstruction at the polar (111)-oriented oxide interface
Abstract
Atomically flat (111) interfaces between insulating perovskite oxides provide a landscape for new electronic phenomena. For example, the graphene-like coordination between interfacial metallic ion layer pairs can lead to topologically protected states [Xiao et al., Nat. Commun. 2, 596 (2011) and A. Rüegg and G. A. Fiete, Phys. Rev. B 84, 201103 (2011)]. The metallic ion/metal oxide bilayers that comprise the unit cell of the perovskite (111) heterostructures require the interface to be polar, generating an intrinsic polar discontinuity [Chakhalian et al., Nat. Mater. 11, 92 (2012)]. Here, we investigate epitaxial heterostructures of (111)-oriented LaAlO3/SrTiO3 (LAO/STO). We find that during heterostructure growth, the LAO overlayer eliminates the structural reconstruction of the STO (111) surface with an electronic reconstruction, which determines the properties of the resulting two-dimensional conducting gas. This is confirmed by transport measurements, direct determination of the structure and atomic charge from coherent Bragg rod analysis, and theoretical calculations of electronic and structural characteristics. Interfacial behaviors of the kind discussed here may lead to new growth control parameters useful for electronic devices.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Mar 01, 2022
- Source ID
- 10.1063/5.0067445
Entities
People
- Chang-Beom Eom
- Chung Wung Bark
- Dillon Fong
- E. Y. Tsymbal
- Huibin Zhou
- J. Podkaminer
- Le Xie
- M. S. Rzchowski
- N. Campbell
- Sangwoo Ryu
- T. Hernandez
- Tula R Paudel
- X. Q. Pan
- Yinglong Zhang
Organizations
- Air Force Office of Scientific Research
- Argonne National Laboratory
- Gordon and Betty Moore Foundation
- National Science Foundation
- United States Department of Defense
- University of Michigan
- University of Nebraska–Lincoln
- University of Wisconsin–Madison