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arXiv · 1501.04481

Holographic model for antiferromagnetic quantum phase transition induced by magnetic field

Rong-Gen Cai·Run-Qiu Yang·F. V. Kusmartsev
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Abstract

We propose a gravity dual of antiferromagnetic quantum phase transition (QPT) induced by magnetic field and study the critical behavior around the quantum critical point (QCP). It turns out that the boundary critical theory is a strong coupling theory with dynamic exponent $z=2$ and that the hyperscaling law is violated and logarithmic corrections appear near the QCP. Some novel scaling relations are predicated, which can be tested by experiment data in future. We also make some comparison with experimental data on low-dimensional magnets BiCoPO$_5$ and pyrochlores Er$_{2-2x}$Y$_{2x}$Ti$_2$O$_7$.

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Rong-Gen Cai, Run-Qiu Yang, F. V. Kusmartsev. 2015-10-09. Holographic model for antiferromagnetic quantum phase transition induced by magnetic field. https://doi.org/10.1103/physrevd.92.086001

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