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Theory of Mott insulator/band insulator heterostructure

Satoshi Okamoto·Andrew J. Millis
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Abstract

A theory of heterostructures comprised of LaTiO$_3$ (a Mott insulator) and SrTiO$_3$ (a band insulator) is presented. The band structure of the Ti $d$% -electrons is treated with a nearest neighbor tight-binding approximation; the electric fields arising from the La$^{3+}$/Sr$^{2+}$ charge difference and the carriers are treated within a Hartree approximation; and the on-site interactions are treated by unrestricted Hartree-Fock. The phase diagram as a function of interaction strength and layer number is determined and predictions are made for optical conductivity experiments. A note worthy finding is that the edges of the heterostructure are generally metallic.

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Satoshi Okamoto, Andrew J. Millis. 2004-04-13. Theory of Mott insulator/band insulator heterostructure. https://doi.org/10.1103/physrevb.70.075101

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