Two-Dimensional Electron Gas at the N-type Interface of the LaAlO3/SrTiO3 Hetero-Structure: A First Principle Study
نویسندگان
چکیده
We examine the formation of the two-dimensional electron gas (2-DEG) at the n-type interface of two band insulators LaAlO3 (LAO) and SrTiO3 (STO) by increasing the thickness of the LAO layers in the framework of the density functional theory (DFT). It has been shown that a metal-insulator phase transition occurs in the 2-DEG when the LAO layers reach to a critical thickness dc = 4 monolayers. The increase of the LAO layers enhances the LAO potential so that electrons can transfer from the LAO valence band to the STO conduction band, which confines conducting electrons only in the STO substrate.
منابع مشابه
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