TY - JOUR
T1 - Robust Electronic Structure of Manganite-Buffered Oxide Interfaces with Extreme Mobility Enhancement
AU - Li, Hang
AU - Gan, Yulin
AU - Husanu, Marius-Adrian
AU - Dahm, Rasmus Tindal
AU - Christensen, Dennis Valbjørn
AU - Radovic, Milan
AU - Sun, Jirong
AU - Shi, Ming
AU - Shen, Baogen
AU - Pryds, Nini
AU - Chen, Yunzhong
PY - 2022
Y1 - 2022
N2 - The electronic structure as well as the mechanism underlying the high-mobility two-dimensional electron gases (2DEGs) at complex oxide interfaces remain elusive. Herein, using soft X-ray angle-resolved photoemission spectroscopy (ARPES), we present the band dispersion of metallic states at buffered LaAlO3/SrTiO3 (LAO/STO) heterointerfaces where a single-unit-cell LaMnO3 (LMO) spacer not only enhances the electron mobility but also renders the electronic structure robust toward X-ray radiation. By tracing the evolution of band dispersion, orbital occupation, and electron-phonon interaction of the interfacial 2DEG, we find unambiguous evidence that the insertion of the LMO buffer strongly suppresses both the formation of oxygen vacancies as well as the electron-phonon interaction on the STO side. The latter effect makes the buffered sample different from any other STO-based interfaces and may explain the maximum mobility enhancement achieved at buffered oxide interfaces.
AB - The electronic structure as well as the mechanism underlying the high-mobility two-dimensional electron gases (2DEGs) at complex oxide interfaces remain elusive. Herein, using soft X-ray angle-resolved photoemission spectroscopy (ARPES), we present the band dispersion of metallic states at buffered LaAlO3/SrTiO3 (LAO/STO) heterointerfaces where a single-unit-cell LaMnO3 (LMO) spacer not only enhances the electron mobility but also renders the electronic structure robust toward X-ray radiation. By tracing the evolution of band dispersion, orbital occupation, and electron-phonon interaction of the interfacial 2DEG, we find unambiguous evidence that the insertion of the LMO buffer strongly suppresses both the formation of oxygen vacancies as well as the electron-phonon interaction on the STO side. The latter effect makes the buffered sample different from any other STO-based interfaces and may explain the maximum mobility enhancement achieved at buffered oxide interfaces.
KW - Oxide interfaces
KW - High mobility 2DEG
KW - Electronic structure
KW - Electron−phonon interaction
KW - Resonant angle-resolved photoemission spectroscopy
U2 - 10.1021/acsnano.2c00609
DO - 10.1021/acsnano.2c00609
M3 - Journal article
C2 - 35312282
SN - 1936-0851
VL - 16
SP - 6437
EP - 6443
JO - ACS Nano
JF - ACS Nano
IS - 4
ER -