Effect of pressure on the magnetoresistance and magnetostriction of heavy fermion materials

The magnetoresistance (MR) and magnetostriction (MS) have been measured at high pressure for heavy fermion materials CeInCu 2 and CeAl 3 . It is found that the sign of MR of CeInCu 2 at 4.2 K changes from negative to positive around 1 GPa, which indicates that the system enters a coherent state. MS of CeInCu 2 and CeAl 3 is affected strongly by an application of pressure. The decrease in magnitude of MS is explained well by assuming the large enhancement of Kondo temperature T K .