Neutron Diffraction Study of the Magnetic Ordering of Low Carrier Kondo Lattice System CeAs under High Pressure

Abstract

Neutron diffraction measurements were performed on CeAs under highpressure. Above the critical pressure, P_c=1.1 GPa, twomagnetically ordered phases appear. The ferromagnetic ordering isestablished in the upper temperature phase. The type-I ordering isestablished in the lower temperature phase in addition to theferromagnetic ordering, which brings about the canted spinstructure. The temperature dependence of the Bragg intensity of thetype-I ordering has a long tail above the Néel temperature. Theferromagnetic moment increases with increasing pressure, while theantiferromagnetic moment decreases particularly above 2.0 GPa. Thetotal magnetic moment, which is the expected Γ₇ valuebelow P_c, decreases abruptly at P_c.