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arXiv · 0903.4820

Half-metallic semiDirac point generated by quantum confinement in TiO$_2$/VO$_2$ nanostructures

Victor Pardo·Warren E. Pickett
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Abstract

Multilayer VO$_2$/TiO$_2$ nanostructures ($d^1$ - $d^0$ interfaces with no polar discontinuity) are studied with first principles density functional methods including structural relaxation. Quantum confinement of the {\it half metallic} VO$_2$ slab within insulating TiO$_2$ produces an unexpected and unprecendented two-dimensional new state, with a {\it semiDirac} point Fermi surface: spinless charge carriers are effective-mass like along one principal axis, but are massless along the other. Effects of interface imperfection are addressed.

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Victor Pardo, Warren E. Pickett. 2009-03-27. Half-metallic semiDirac point generated by quantum confinement in TiO$_2$/VO$_2$ nanostructures. https://doi.org/10.1103/physrevlett.102.166803

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