Pressure Dependence of the Magnetization of $\mathrm{U}{\mathrm{Ru}}_{2}{\mathrm{Si}}_{2}$

The ground state of URu2Si2 changes from so-called hidden order (HO) to large-moment antiferromagnetism (LMAF) upon applying hydrostatic pressure in excess of $\sim$14kbar. We report the dc magnetization M(B,T,p) of URu2Si2 for magnetic fields B up to 12T, temperatures T in the range 2\textendash{}100K, and pressure p up to 17kbar. Remarkably, characteristic scales such as the coherence temperature T$∗$, the transition temperature T0, and the anisotropy in the magnetization depend only weakly on the applied pressure. However, the discontinuity in $\partial$M$\slash\partial$T at T0, which measures the magnetocaloric effect, decreases nearly 50% upon applying 17kbar for M and B parallel to the tetragonal c axis, while it increases 15-fold for the a axis. Our findings suggest that the HO and LMAF phases have an astonishing degree of similarity in their physical properties, but a key difference is the magnetocaloric effect near T0 in the basal plane.     «

The ground state of URu2Si2 changes from so-called hidden order (HO) to large-moment antiferromagnetism (LMAF) upon applying hydrostatic pressure in excess of $\sim$14kbar. We report the dc magnetization M(B,T,p) of URu2Si2 for magnetic fields B up to 12T, temperatures T in the range 2\textendash{}100K, and pressure p up to 17kbar. Remarkably, characteristic scales such as the coherence temperature T$∗$, the transition temperature T0, and the anisotropy in the magnetization depend only weakly on...     »