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Itinerant electron metamagnetism in LaCo$_9$Si$_4$

H. Michor·M. El-Hagary·M. DellaMea·M. W Pieper·M. Reissner·G. Hilscher·S. Khmelevskyi·P. Mohn·G. Schneider·G. Giester·P. Rogl
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Abstract

The strongly exchange enhanced Pauli paramagnet LaCo$_9$Si$_4$ is found to exhibit an itinerant metamagnetic phase transition with indications for metamagnetic quantum criticality. Our investigation comprises magnetic, specific heat, and NMR measurements as well as ab-initio electronic structure calculations. The critical field is about 3.5 T for $H||c$ and 6 T for $H\bot c$, which is the lowest value ever found for rare earth intermetallic compounds. In the ferromagnetic state there appears a moment of about 0.2 $μ_B$/Co at the $16k$ Co-sites, but sigificantly smaller moments at the 4d and $16l$ Co-sites.

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H. Michor, M. El-Hagary, M. DellaMea, M. W Pieper, M. Reissner, G. Hilscher, S. Khmelevskyi, P. Mohn, G. Schneider, G. Giester, P. Rogl. 2003-12-22. Itinerant electron metamagnetism in LaCo$_9$Si$_4$. https://doi.org/10.1103/physrevb.69.081404

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