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arXiv · 1105.2102

Magnetic properties of lightly doped antiferromagnetic YBa$_{2}$Cu$_{3}$O$_{y}$

O. P. Sushkov
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Abstract

The present work addresses YBa$_{2}$Cu$_{3}$O$_{y}$ at doping below x=6% where the compound is a collinear antiferromagnet. In this region YBa$_{2}$Cu$_{3}$O$_{y}$ is a normal conductor with a finite resistivity at zero temperature. The value of the staggered magnetization at zero temperature is 0.6\mu_B, the maximum value allowed by spin quantum fluctuations. The staggered magnetization is almost independent of doping. On the other hand, the Neel temperature decays very quickly from T_N=420K at x=0 to practically zero at x = 0.06. The present paper explains these remarkable properties and demonstrates that the properties result from the physics of a lightly doped Mott insulator with small hole pockets. Nuclear quadrupole resonance data are also discussed. The data shed light on mechanisms of stability of the antiferromagnetic order at x < 6%.

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O. P. Sushkov. 2011-05-11. Magnetic properties of lightly doped antiferromagnetic YBa$_{2}$Cu$_{3}$O$_{y}$. https://doi.org/10.1103/physrevb.84.094532

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