Effect of pressure on the superconductivity and magnetism in HoNi 2B2C

Abstract

The electrical resistivity of single crystalline HoNi2B 2C 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. © 2010 IOP Publishing Ltd.