Magnetic Properties of a Pressure-induced Superconductor UGe${}_2$

Abstract

We performed the DC-magnetization and neutron scattering experiments under pressure {\it P} for a pressure-induced superconductor UGe${}_2$. We found that the magnetic moment is enhanced at a characteristic temperature {\it T}${}^{\ast }$ in the ferromagnetic state, where {\it T}${}^{\ast }$ is smaller than a Curie temperature {\it T}${}_{\mathrm{C}}$. This enhancement becomes remarkable in the vicinity of {\it P}${}_{\mathrm{C}}^{\ast }$ = 1.20 GPa, where {\it T}${}^{\ast }$ becomes 0 K and the superconducting transition temperature {\it T}${}_{\mathrm{SC}}$ shows a maximum. The characteristic temperature {\it T}${}^{\ast }$, which decreases with increasing pressure, also depends on the magnetic field.

To be published in J.Phys.Soc.Jpn