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arXiv · 0902.0945

Itinerant antiferromagnetism in BaCr$_2$As$_2$

D. J. Singh·A. S. Sefat·M. A. McGuire·B. C. Sales·D. Mandrus·L. H. VanBebber·V. Keppens
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Abstract

We report single crystal synthesis, specific heat and resistivity measurements and electronic structure calculations for BaCr$_2$As$_2$. This material is a metal with itinerant antiferromagnetism, similar to the parent phases of Fe-based high temperature superconductors, but differs in magnetic order. Comparison of bare band structure density of states and the low temperature specific heat implies a mass renormalization of $\sim$ 2. BaCr$_2$As$_2$ shows stronger transition metal - pnictogen covalency than the Fe compounds, and in this respect is more similar to BaMn$_2$As$_2$. This provides an explanation for the observation that Ni and Co doping is effective in the Fe-based superconductors, but Cr or Mn doping is not.

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D. J. Singh, A. S. Sefat, M. A. McGuire, B. C. Sales, D. Mandrus, L. H. VanBebber, V. Keppens. 2009-02-16. Itinerant antiferromagnetism in BaCr$_2$As$_2$. https://doi.org/10.1103/physrevb.79.094429

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