Effect of Hydrostatic Pressure on the Magnetic Susceptibility of a Ag: Mn Spin-Glass

The magnetic susceptibility of a Ag-3-at.%-Mn spin-glass has been measured under hydrostatic pressure to 15 kbar. The spin-glass freezing temperature $T_0$ increases with pressure at the rate $\frac{d{T}_0}{\mathrm{dP}}\simeq +42\mathrm{}\pm 4$ mK/kbar. This pressure dependence is clear evidence that the Ruderman-Kittel-Kasuya-Yosida (RKKY) interaction, and not the magnetic dipole interaction, is responsible for spin-glass freezing at $T_0$. The present results thus support those models of spin-glass freezing which are based solely on RKKY interactions between spins.