Abstract
The electrical resistivity of single crystalline HoNi2B2C has been measured under pressure up to 3.0 GPa. At ambient pressure, the resistivity shows sudden drop below Tc = 8.8 K, and becomes zero below 8.0 K. At 2.0 GPa, it drops below Tc = 8.1 K, becomes zero below 7.2 K, and shows a peak around 5.9 K due to the antiferromagnetic (AFM) order. Then it becomes zero again below 5.7 K. It is observed that the superconductivity is affected strongly by changing current density. Tc with 5.6 A/cm2 decreases with increasing pressure. On the other hand, Tc increases when a current density is close to the critical current density Jc = 63.9 A/cm2 with increasing pressure up to 3.0 GPa.