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Magneto-thermodynamics of the spin-1/2 Kagome antiferromagnet

Philippe Sindzingre·Gregoire Misguich·Claire Lhuillier·Bernard Bernu·Laurent Pierre·Christian Waldtmann·Hans U. Everts
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Abstract

In this paper, we use a new hybrid method to compute the thermodynamic behavior of the spin-1/2 Kagome antiferromagnet under the influence of a large external magnetic field. We find a T^2 low-temperature behavior and a very low sensitivity of the specific heat to a strong external magnetic field. We display clear evidence that this low temperature magneto-thermal effect is associated to the existence of low-lying fluctuating singlets, but also that the whole picture (T^2 behavior of Cv and thermally activated spin susceptibility) implies contribution of both non magnetic and magnetic excitations. Comparison with experiments is made.

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Philippe Sindzingre, Gregoire Misguich, Claire Lhuillier, Bernard Bernu, Laurent Pierre, Christian Waldtmann, Hans U. Everts. 2000-02-28. Magneto-thermodynamics of the spin-1/2 Kagome antiferromagnet. https://doi.org/10.1103/physrevlett.84.2953

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