Duality and degeneracy lifting in two-dimensional electron liquids on SrTiO3(001)
Two-dimensional electron liquids (2DELs) have increasing technological relevance for ultrafast electronics and spintronics, yet significant gaps in their fundamental understanding are exemplified on the prototypical SrTiO<sub>3</sub>. We correlate the exact SrTiO<sub>3</sub>(001) surface structure with distinct 2DELs through combined microscopic angle-resolved photoemission spectroscopy and non-contact atomic force microscopy on truly bulk-terminated surfaces that alleviate structural uncertainties inherent to this long-studied system. The SrO termination is shown to develop a 2DEL following the creation of oxygen vacancies, unlike the intrinsically metallic TiO<sub>2</sub> termination. Differences in degeneracy of the 2DELs, with nearly the same band filling and identical band bending, are assigned to polar distortions of the Ti atoms in combination with spin order, supported with the extraction of fundamental electron-phonon coupling strength. These results not only resolve the ambiguities regarding 2DELs on SrTiO<sub>3</sub> thus far, but also pave the way to manipulating band filling and spin order in oxide 2DELs in general.
Authors
- J. Hugo Dil (ORCID: https://orcid.org/0000-0002-6016-6120)
- Michael Schmid (ORCID: https://orcid.org/0000-0003-3373-9357)
- Craig Polley (ORCID: https://orcid.org/0000-0002-9893-2767)
- M. Radović (ORCID: https://orcid.org/0000-0003-4042-9648)
- Samuel Poncé (ORCID: https://orcid.org/0000-0003-1159-8389)
- Igor Sokolović (ORCID: https://orcid.org/0000-0003-1357-396X)
- Ulrike Diebold (ORCID: https://orcid.org/0000-0003-0319-5256)
- Fei Guo (ORCID: https://orcid.org/0000-0002-3748-4016)
- Eduardo B. Guedes (ORCID: https://orcid.org/0000-0001-9638-0447)
- Martin Setvín (ORCID: https://orcid.org/0000-0002-1210-7740)
- Thomas Waas (ORCID: https://orcid.org/0000-0002-8560-4318)
Institutions
- TU Wien (AT)
- Lund University (SE)
- Charles University (CZ)
- Paul Scherrer Institute (CH)
- European Theoretical Spectroscopy Facility (BE)
- MAX IV Laboratory (SE)
- Walloon Excellence in Lifesciences and Biotechnology (BE)
- École Polytechnique Fédérale de Lausanne (CH)
Publication Details
- Journal
- Nature Communications
- Published
- 2025-05-17
- DOI
- https://doi.org/10.1038/s41467-025-59258-4
- Citations
- 1
- Primary Topic
- Electronic and Structural Properties of Oxides
- Type
- article
- Field-Weighted Citation Impact
- 0.52
Funders
- National Science Foundation
- Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung
- Grantová Agentura České Republiky
- VINNOVA
- Svenska Forskningsrådet Formas
- Austrian Science Fund
- Fonds De La Recherche Scientifique - FNRS
- Vetenskapsrådet