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arXiv · 0905.0467

Asymmetric quintuplet condensation in the frustrated S=1 spin dimer compound Ba3Mn2O8

E. C. Samulon·Y. Kohama·R. D. McDonald·M. C. Shapiro·K. A. Al-Hassanieh·C. D. Batista·M. Jaime·I. R. Fisher
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Abstract

Ba3Mn2O8 is a spin-dimer compound based on pairs of S = 1, 3d2, Mn5+ ions arranged on a triangular lattice. Antiferromagnetic intradimer exchange leads to a singlet ground state in zero-field, with excited triplet and quintuplet states at higher energy. High field thermodynamic measurements are used to establish the phase diagram, revealing a substantial asymmetry of the quintuplet condensate. This striking effect, all but absent for the triplet condensate, is due to a fundamental asymmetry in quantum fluctuations of the paramagnetic phases near the various critical fields.

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E. C. Samulon, Y. Kohama, R. D. McDonald, M. C. Shapiro, K. A. Al-Hassanieh, C. D. Batista, M. Jaime, I. R. Fisher. 2009-07-23. Asymmetric quintuplet condensation in the frustrated S=1 spin dimer compound Ba3Mn2O8. https://doi.org/10.1103/physrevlett.103.047202

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