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arXiv · 0902.4229

Magnetic field-induced phase transitions in a weakly coupled s = 1/2 quantum spin dimer system Ba$_{3}$Cr$_{2}$O$_{8}$

M. Kofu·H. Ueda·H. Nojiri·Y. Oshima·T. Zenmoto·K. Rule·S. Gerischer·B. Lake·C. D. Batista·Y. Ueda·S. -H. Lee
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Abstract

By using bulk magnetization, electron spin resonance (ESR), heat capacity, and neutron scattering techniques, we characterize the thermodynamic and quantum phase diagrams of Ba$_3$Cr$_2$O$_8$. Our ESR measurements indicate that the low field paramagnetic ground state is a mixed state of the singlet and the S$_z$ = 0 triplet for $H \perp c$. This suggests the presence of an intra-dimer Dzyaloshinsky-Moriya (DM) interaction with a DM vector perpendicular to the c-axis.

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M. Kofu, H. Ueda, H. Nojiri, Y. Oshima, T. Zenmoto, K. Rule, S. Gerischer, B. Lake, C. D. Batista, Y. Ueda, S. -H. Lee. 2009-02-24. Magnetic field-induced phase transitions in a weakly coupled s = 1/2 quantum spin dimer system Ba$_{3}$Cr$_{2}$O$_{8}$. https://doi.org/10.1103/physrevlett.102.177204

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