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Interface polarization model for a 2-dimensional electron gas at the BaSnO3/LaInO3 interface.

ABSTRACT: In order to explain the experimental sheet carrier density n2D at the interface of BaSnO3/LaInO3, we consider a model that is based on the presence of interface polarization in LaInO3 which extends over 2 pseudocubic unit cells from the interface and eventually disappears in the next 2 unit cells. Considering such interface polarization in calculations based on 1D Poisson-Schrödinger equations, we consistently explain the dependence of the sheet carrier density of BaSnO3/LaInO3 heterinterfaces on the thickness of the LaInO3 layer and the La doping of the BaSnO3 layer. Our model is supported by a quantitative analysis of atomic position obtained from high resolution transmission electron microscopy which evidences suppression of the octahedral tilt and a vertical lattice expansion in LaInO3 over 2-3 pseudocubic unit cells at the coherently strained interface.

SUBMITTER: Kim YM

PROVIDER: S-EPMC6838460 | biostudies-literature | 2019 Nov

REPOSITORIES: biostudies-literature

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Interface polarization model for a 2-dimensional electron gas at the BaSnO3/LaInO3 interface.

Kim Young Mo YM Markurt T T Kim Youjung Y Zupancic M M Shin Juyeon J Albrecht M M Char Kookrin K

Scientific reports 20191107 1

In order to explain the experimental sheet carrier density n2D at the interface of BaSnO3/LaInO3, we consider a model that is based on the presence of interface polarization in LaInO3 which extends over 2 pseudocubic unit cells from the interface and eventually disappears in the next 2 unit cells. Considering such interface polarization in calculations based on 1D Poisson-Schrödinger equations, we consistently explain the dependence of the sheet carrie ...[more]

PMID: 31700133

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