Pressure - Temperature Magnetic Phase Diagram of TbNiSn

抄録

The electrical resistivity of TbNiSn for the b-axis has been measured under hydrostatic pressures up to 22 kbar. Resistivity anomalies associated with the successive magnetic transitions are observed. At P=Okbar, the transitions at T_N (=18. 5 K) and T₃ (=7. 6 K) are second order whereas the transition at T₂ (=6. 0 K) is first order. We observe that the resistivity drops discontinuously at T₂ and accompanies thermal hysteresis. There is not appreciable change in the resistivity at T₁ (=2. 2 K). The pressure-temperature magnetic phase diagram has been constructed. All the transition temperatures first decrease, take minima at 3 kbar and then increase with increasing pressure. It should be also noted that the T₃ line is merged in the T₂ line above 17 kbar. Total spin disorder resistivity is pressure independent.