Dichotomy of the photo-induced 2-dimensional electron gas on SrTiO3 surface terminationsShow others and affiliations
2019 (English)In: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 116, no 34, p. 16687-16691Article in journal (Refereed) Published
Abstract [en]
Oxide materials are important candidates for the next generation of electronics due to a wide array of desired properties, which they can exhibit alone or when combined with other materials. While SrTiO3 (STO) is often considered a prototypical oxide, it, too, hosts a wide array of unusual properties, including a 2-dimensional electron gas (2DEG), which can form at the surface when exposed to ultraviolet (UV) light. Using layer-by-layer growth of high-quality STO films, we show that the 2DEG only forms with the SrO termination and not with the TiO2 termination, contrary to expectation. This dichotomy of the observed angle-resolved photoemission spectroscopy (ARPES) spectra is similarly seen in BaTiO3 (BTO), in which the 2DEG is only observed for BaO-terminated films. These results will allow for a deeper understanding and better control of the electronic structure of titanate films, substrates, and heterostructures.
Place, publisher, year, edition, pages
NATL ACAD SCIENCES , 2019. Vol. 116, no 34, p. 16687-16691
Keywords [en]
2-dimensional electron gas; molecular beam epitaxy; strontium titanate; termination control
National Category
Condensed Matter Physics
Identifiers
URN: urn:nbn:se:liu:diva-173799DOI: 10.1073/pnas.1821937116ISI: 000481935500010PubMedID: 31391304OAI: oai:DiVA.org:liu-173799DiVA, id: diva2:1535263
2021-03-082021-03-082021-03-08Bibliographically approved