Successive magnetic transitions of PrRh2 single crystals

Measurements of the magnetization and the specific heat were performed on a PrRh2 single crystal. A strong magnetic anisotropy with the easy magnetization direction of the c-axis is observed. Four anomalies appear in the temperature dependence of magnetic susceptibility along the c-axis; a cusp at TN=52 K, a high peak at T3=38 K, a shoulder at T2=33 K and a small peak at T1=4 K are observed, indicating magnetic transitions. The specific heat also shows four anomalies at the temperatures where the magnetic anomalies appear, confirming the occurrence of successive magnetic transitions. A clear two-step metamagnetic process appears along the easy magnetization direction of the c-axis at low temperatures. The magnetization in the first step is almost constant and is corresponds to (1/5) Ms (Ms: saturation magnetization), indicating that this field-induced phase has a long period and a stable magnetic structure. A metamagnetic process is hypothesized on the basis of the magnetic structure. The B001 − T phase diagram is constructed.