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arXiv · 1106.5671

DFT+U study of magnetic order in doped La$_2$CuO$_4$ crystals

Simon Pesant·Michel Côté
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Abstract

This article presents the results of several magnetic phases of doped La$_{2-x}$Sr$_x$CuO$_4$ using density-functional theory with an added Hubbard term (DFT+U). Doping factors from $x=0$ to 0.25 were examined. We found that a bond centered stripe is the magnetic ground state for $x=1/8$ and $x=1/4$. No stable stripe order was found for $x=1/6$. Analysis of the electron density revealed that apical oxygen atoms, those located above and below the copper atoms in the CuO$_2$ planes, hold a non negligible part of the holes at large doping and present a small spin polarization. Finally, the charge reorganization caused by the magnetic stripe modulation was studied for bond centered and atom centered stripes.

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Simon Pesant, Michel Côté. 2011-06-28. DFT+U study of magnetic order in doped La$_2$CuO$_4$ crystals. https://doi.org/10.1103/physrevb.84.085104

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