On the contrasting spin dynamics of $La_{2-x}Sr_xCuO_4$, $Nd_{2-x}Ce_xCuO_4$ and $YBa_2Cu_3O_{6+x}$ near half filling

Andrey V. Chubukov; Karen A. Musaelian

doi:10.1088/0953-8984/7/1/012

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arXiv · cond-mat/9407074

On the contrasting spin dynamics of $La_{2-x}Sr_xCuO_4$, $Nd_{2-x}Ce_xCuO_4$ and $YBa_2Cu_3O_{6+x}$ near half filling

Andrey V. Chubukov·Karen A. Musaelian

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Abstract

We present simple calculations which show that incommensurability upon doping and the width of the magnetically ordered phase in Mott-Hubbard insulators depend strongly on the location of the hole/electron pockets in the Brillouin zone. For $LaSrCuO$ systems, we found the pockets at $(\pm π/2,\pm π/2)$, in which case the corrections to the antiferromagnetic spin stiffness grow with doping and destroy the commensurate antiferromagnetic ordering already at a very small doping. On the other hand, in $NdCeCuO$, the hole pockets are located at $(π,0)$ and the symmetry related points, in which case the corrections to the stiffness scale linearly with the density of carriers and do not destroy commensurate spin ordering. For $YBCuO$, systems the situation is less certain, but our results favor hole pockets at $(π/2,π/2)$. We also discuss briefly the tendency towards phase separation.

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Andrey V. Chubukov, Karen A. Musaelian. 1994-07-18. On the contrasting spin dynamics of $La_{2-x}Sr_xCuO_4$, $Nd_{2-x}Ce_xCuO_4$ and $YBa_2Cu_3O_{6+x}$ near half filling. https://doi.org/10.1088/0953-8984%2F7%2F1%2F012

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