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arXiv · 0811.2523

Renormalized behavior and proximity to a magnetic quantum critical point in BaCo$_2$As$_2$

A. S. Sefat·D. J. Singh·R. Jin·M. A. McGuire·B. C. Sales·D. Mandrus
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Abstract

We report synthesis and single crystal measurements of magnetic, transport and thermal properties of single crystalline BaCo$_2$As$_2$ as well as first principles calculations of the electronic structure and magnetic behavior. These results show that BaCo$_2$As$_2$ is a highly renormalized paramagnet in proximity to a quantum critical point, presumably of ferromagnetic character and that BaFeNiAs$_2$ behaves similarly. These results are discussed in relation to the properties of Ba(Fe,Co)$_2$As$_2$ and Ba(Fe,Ni)$_2$As$_2$, which are superconducting for low Co and Ni concentrations.

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A. S. Sefat, D. J. Singh, R. Jin, M. A. McGuire, B. C. Sales, D. Mandrus. 2008-11-15. Renormalized behavior and proximity to a magnetic quantum critical point in BaCo$_2$As$_2$. https://doi.org/10.1103/physrevb.79.024512

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