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Influence of In-Gap States on the Formation of Two-Dimensional Election Gas at ABO3/SrTiO3 Interfaces.

ABSTRACT: We explored in-gap states (IGSs) in perovskite oxide heterojunction films. We report that IGSs in these films play a crucial role in determining the formation and properties of interfacial two-dimensional electron gas (2DEG). We report that electron trapping by IGSs opposes charge transfer from the film to the interface. The IGS in films yielded insulating interfaces with polar discontinuity and explained low interface carrier density of conducting interfaces. An ion trapping model was proposed to explain the physics of the IGSs and some experimental findings, such as the unexpected formation of 2DEG at the initially insulating LaCrO3/SrTiO3 interface and the influence of substitution layers on 2DEG.

SUBMITTER: Li CJ

PROVIDER: S-EPMC5760580 | biostudies-literature | 2018 Jan

REPOSITORIES: biostudies-literature

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Influence of In-Gap States on the Formation of Two-Dimensional Election Gas at ABO<sub>3</sub>/SrTiO<sub>3</sub> Interfaces.

Li Cheng-Jian CJ Xue Hong-Xia HX Qu Guo-Liang GL Shen Sheng-Chun SC Hong Yan-Peng YP Wang Xin-Xin XX Liu Ming-Rui MR Jiang Wei-Min WM Badica Petre P He Lin L Dou Rui-Fen RF Xiong Chang-Min CM Lü Wei-Ming WM Nie Jia-Cai JC

Scientific reports 20180109 1

We explored in-gap states (IGSs) in perovskite oxide heterojunction films. We report that IGSs in these films play a crucial role in determining the formation and properties of interfacial two-dimensional electron gas (2DEG). We report that electron trapping by IGSs opposes charge transfer from the film to the interface. The IGS in films yielded insulating interfaces with polar discontinuity and explained low interface carrier density of conducting interfaces. An ion trapping model was proposed ...[more]

PMID: 29317754

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