Emergent ferromagnetism andT-linear scattering inUSb2at high pressure

Abstract

The material ${\mathrm{USb}}_{2}$ is a correlated, moderately heavy-electron compound within the uranium dipnictide (${\mathrm{UX}}_{2}$) series. It is antiferromagnetic with a relatively high transition temperature ${T}_{N}=204\phantom{\rule{4pt}{0ex}}\mathrm{K}$ and a large U-U separation. While the uranium atoms in the lighter dipnictides are considered to be localized, those of ${\mathrm{USb}}_{2}$ exhibit hybridization and itineracy, promoting uncertainty as to the continuity of the magnetic order within the ${\mathrm{UX}}_{2}$. We have explored the evolution of the magnetic order by employing magnetotransport measurements as a function of pressure and temperature. We find that the ${T}_{N}$ in ${\mathrm{USb}}_{2}$ is enhanced, moving towards that of its smaller sibling ${\mathrm{UAs}}_{2}$. But, long before reaching a ${T}_{N}$ as high as ${\mathrm{UAs}}_{2}$, the antiferromagnetism of ${\mathrm{USb}}_{2}$ is abruptly destroyed in favor of another magnetic ground state. We identify this pressure-induced ground state as being ferromagnetic based on the appearance of a strong anomalous Hall effect in the transverse resistance in magnetic field. With pressure, this emergent ferromagnetic state is suppressed and ultimately destroyed in favor of a non-Fermi-liquid ground state.