Atomic-resolved depth profile of strain and cation intermixing around LaAlO3/SrTiO3 interfaces.
Novel behavior has been observed at the interface of LaAlO3/SrTiO3 heterostructures such as two dimensional metallic conductivity, magnetic scattering and superconductivity. However, both the origins and quantification of such behavior have been complicated due to an interplay of mechanical, chemical and electronic factors. Here chemical and strain profiles near the interface of LaAlO3/SrTiO3 heterostructures are correlated. Conductive and insulating samples have been processed, with thicknesses respectively above and below the commonly admitted conductivity threshold. The intermixing and structural distortions within the crystal lattice have been quantitatively measured near the interface with a depth resolution of unit cell size. A strong link between intermixing and structural distortions at such interfaces is highlighted: intermixing was more pronounced in the hetero-couple with conductive interface, whereas in-plane compressive strains extended deeper within the substrate of the hetero-couple with the insulating interface. This allows a better understanding of the interface local mechanisms leading to the conductivity.
MINES ParisTech, PSL Research University, MAT - Centre des matériaux, CNRS UMR 7633, BP 87 91003 Evry, France.
H
H
Zaid
MINES ParisTech, PSL Research University, MAT - Centre des matériaux, CNRS UMR 7633, BP 87 91003 Evry, France.
M H
MH
Berger
Université Grenoble Alpes, INAC-SP2M, LEMMA, F-38000 Grenoble, France.|CEA, INAC-SP2M, LEMMA, F-38000 Grenoble, France.
D
D
Jalabert
Laboratoire de Physique des Solides, Université Paris Sud, Bât 510, 91405 Orsay, France.
M
M
Walls
Departments of Materials Science and Engineering, Case Western Reserve University, Cleveland, Ohio, USA.
R
R
Akrobetu
Departments of Physics, Case Western Reserve University, Cleveland, Ohio, USA.
I
I
Fongkaew
Departments of Physics, Case Western Reserve University, Cleveland, Ohio, USA.
W R L
WR
Lambrecht
Departments of Physics, Case Western Reserve University, Cleveland, Ohio, USA.
N J
NJ
Goble
Departments of Physics, Case Western Reserve University, Cleveland, Ohio, USA.
X P A
XP
Gao
NIMBE, CEA, CNRS, Université Paris-Saclay, CEA Saclay 91191 Gif sur Yvette, Cedex, France.
P
P
Berger
Departments of Materials Science and Engineering, Case Western Reserve University, Cleveland, Ohio, USA.
A
A
Sehirlioglu