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CsMn(Br_xI_{1-x})_3: Crossover from an XY to an Ising Chiral Antiferromagnet

R. Buegel·J. Wosnitza·H. v. Loehneysen·T. Ono·H. Tanaka
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Abstract

We report on high-resolution specific-heat and magnetocaloric-effect measurements of the triangular-lattice antiferromagnets CsMn(Br_xI_{1-x})_3 with different x. The evolution of the magnetic phase diagrams from the easy-axis system for x = 0 to the easy-plane system for x = 1 was studied in detail. The specific-heat critical exponent alpha of the almost isotropic x = 0.19 system agrees with the value predicted for a chiral Heisenberg scenario. In an applied magnetic field (B = 6 T) a crossover to a weak first-order transition is detected.

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R. Buegel, J. Wosnitza, H. v. Loehneysen, T. Ono, H. Tanaka. 2001-03-01. CsMn(Br_xI_{1-x})_3: Crossover from an XY to an Ising Chiral Antiferromagnet. https://doi.org/10.1103/physrevb.64.094406

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