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arXiv · 0912.3663

Room temperature magnetism in LaVO3/SrVO3 superlattices by geometrically confined doping

Abstract

Based on the Hubbard model of strongly correlated systems, a reduction in the bandwidth of the electrons can yield a substantial change in the properties of the material. One method to modify the bandwidth is geometrically confined doping, i.e. the introduction of a (thin) dopant layer in a material. In this paper, the magnetic properties of LaVO$_3$/SrVO$_3$ superlattices, in which the geometrically confined doping is produced by a one monolayer thick SrVO$_3$ film, are presented. In contrast to the solid solution La$_{1-x}$Sr$_x$VO$_3$, such superlattices have a finite magnetization up to room temperature. Furthermore, the total magnetization of the superlattice depends on the thickness of the LaVO$_3$ layer, indicating an indirect coupling of the magnetization that emerges at adjacent dopant layers. Our results show that geometrically confined doping, like it can be achieved in superlattices, reveals a way to induce otherwise unaccessible phases, possibly even with a large temperature scale.

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U. Luders, W. C. Sheets, A. David, W. Prellier, R. Fresard. 2009-12-18. Room temperature magnetism in LaVO3/SrVO3 superlattices by geometrically confined doping. https://doi.org/10.1103/physrevb.80.241102

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