Magnetic properties of U1-xThxAs and UAs1-xSex compounds

Abstract

The thermal variation of the magnetic susceptibility of U 1-x Th x As and UAs 1-x Se x compounds has been investigated by a mutual inductance technique. The magnetic phase diagram of these two compounds has been determined in zero field. Anomalies as peaks or jumps have been evidenced in the thermal variation of the magnetic susceptibility for both series of compounds, above the ordering temperature. Neutron diffraction experiments are necessary to know if these anomalies are associated with changes in the magnetic structures. For U 1-x Th x As, as for UAs 1-x Se x compounds, additional conduction electrons are provided by thorium and selenium. The similarities between the magnetic behaviour of these compounds show that the conduction electrons play a fundamental role in their magnetic properties Mesure de la variation thermique de la susceptibilite magnetique par une methode d'inductance mutuelle. Determination des diagrammes de phase magnetiques en champ nul. Observation d'anomalies (pics et sauts) au-dessus de la temperature d'ordre. Dans les deux composes, apport d'electrons supplementaires par les atomes Th et Se