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Two successive field-induced spin-flop transitions in single-crystalline CaCo$_{2}$As$_{2}$

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 نشر من قبل Bing Cheng
 تاريخ النشر 2012
  مجال البحث فيزياء
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CaCo$_{2}$As$_{2}$, a ThCr$_{2}$Si$_{2}$-structure compound, undergoes an antiferromagnetic transition at emph{T$_{N}$}=76K with the magnetic moments being aligned parallel to the emph{c} axis. Electronic transport measurement reveals that the coupling between conducting carriers and magnetic order in CaCo$_{2}$As$_{2}$ is much weaker comparing to the parent compounds of iron pnictide. Applying magnetic field along emph{c} axis induces two successive spin-flop transitions in its magnetic state. The magnetization saturation behaviors with emph{textbf{H}$parallel$c} and emph{textbf{H}$parallel$ab} at 10K indicate that the antiferromagnetic coupling along emph{c} direction is very weak. The interlayer antiferromagntic coupling constant emph{J$_{c}$} is estimated to be about 2 meV.



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