Anomalous pressure dependence of magnetoresistance of Cr and Cr–V alloy

Abstract

The magnetoresistances (MRs) of Cr and Cr_0.985V_0.015 (Cr–V) alloy have been measured at high pressures up to 2.0 GPa in order to elucidate the relation between the transport properties and spin density wave (SDW) antiferromagnetic state. The resistance of Cr is found to increase with increasing magnetic field (H). MR ratios of Cr and Cr–V alloy at room temperature are nearly 0% and 0.3% at 7 T, respectively. But at 77 K, these are 70% and 30% at 7 T at ambient pressure, respectively. MR ratio of Cr at 77 K is found to show a peak ∼1.3 GPa but that of Cr–V alloy decreases smoothly with pressure. The origins of the pressure dependence in the magnitude of MR are discussed in connection with the SDW antiferromagnetic states.

Keywords:

• High pressure
• Giant magnetoresistance
• Spin density wave
• Spin flip transition