Study of the ferromagnetic quantum phase transition in Ce${}_{3-x}$Mg${}_x$Co${}_9$

Abstract

The Ce${}_{3-x}$Mg${}_x$Co${}_9$ system evolves from a Pauli paramagnetic ground state for $x=0$ to a ferromagnetic ground state for $x\approx 0.80$ in single phase, polycrystalline samples [Phys. Rev. Applied 9, 024023 (2018)]. In order to better understand this behavior, single crystalline samples of Ce${}_{3-x}$Mg${}_x$Co${}_9$ for \textit{x} = 0.01, 0.16, 0.24, 0.35, 0.43 and 0.50 were grown using the flux growth technique, and electrical transport and magnetic properties were studied. The \textit{T}${}_C$-\textit{x} phase diagram we infer shows that the system has a quantum phase transition near \textit{x} = 0.35, transforming to a ferromagnetic ground state.

13 pages, 13 figures