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Surface termination conversion effect on the electronic structure of two-dimensional electron gas at EuTiO3 surfaces

Sungsoo Hahn1,2, Keun-Yeol Park1, Minkyu Park2, Yeonjae Lee1, Youngdo Kim1, S. H. Rhim3, Celesta S. Chang1, Chanyong Hwang2, and Changyoung Kim1,*

  • *Contact author: changyoung@snu.ac.kr
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Phys. Rev. Materials 10, L021001 – Published 11 February, 2026Erratum Phys. Rev. Materials 10, 069901 (2026)

DOI: https://doi.org/10.1103/dx5k-dwgv

Abstract

We perform in situ angle-resolved photoemission spectroscopy to investigate the effect of surface termination conversion on two-dimensional electron gas (2DEG) at the EuTiO3(001) surface. We successfully engineered EuTiO3 with nearly single TiO2 termination via epitaxial growth on TiO2-terminated SrTiO3, and EuTiO3 with nearly complete EuO termination by inserting a SrRuO3 buffer layer into the heterostructure. The orbital configuration of the 2DEG exhibits a strong dependence on the EuTiO3 termination, and this experimental observation matches our first-principles calculation results very well. Furthermore, we observe the termination dependence of a kink feature in dxy band. This finding implies that many-body interactions, and possibly magnetism, are influenced by the surface termination. Our study not only introduces a method to fabricate surface or interfacial 2DEG system, but also highlights the effect of termination conversion on magnetic 2DEG.

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Erratum

Erratum: Surface termination conversion effect on the electronic structure of two-dimensional electron gas at EuTiO3 surfaces [Phys. Rev. Materials 10, L021001 (2026)]

Sungsoo Hahn, Keun-Yeol Park, Minkyu Park, Yeonjae Lee, Youngdo Kim, S. H. Rhim, Celesta S. Chang, Chanyong Hwang, and Changyoung Kim
Phys. Rev. Materials 10, 069901 (2026)

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Phys. Rev. Materials 10, L021001– Published 11 February, 2026
  • Received 31 July 2025
  • Accepted 23 January 2026
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