Itinerant-electron metamagnetic transition and large magnetovolume effects in La(FexSi1-x)(13) compounds

Magnetic properties and magnetovolume effects have been investigated for itinerant-electron metamagnetic La(FexSi(1-x))(13) compounds. At the Curie temperature T-C1, a first-order magnetic phase transition takes place in the concentration range 0.86less than or equal toxless than or equal to0.88. With increasing Fe concentration, the Curie temperature decreases and the critical temperature of the itinerant-electron metamagnetic (IEM) transition increases, accompanied by a more sharp IEM transition. For the compound with x = 0.88, a large volume change of about 1% follows the thermal induced transition at T-C1. The value of T-C1 is significantly decreased by applying hydrostatic pressure, whereas the pressure dependence of the spontaneous magnetization is relatively small. These results are explained by the negative mode-mode coupling among spin fluctuations.