Enhancing ferromagnetism in the kinetically arrested LaFe12B6 by partial La/Nd substitution

Abstract

The intrinsic magnetic properties of the La0.9Nd0.1Fe12B6 compound have been studied by magnetization measurements. The compound orders ferromagnetically (FM) at the Curie temperature, TC, of ~58 K, which shifts toward higher temperatures with increasing magnetic field. At 2 K isothermal magnetization data indicate a mixed magnetic state with ~2/3 of the material remaining FM and ~1/3 becoming antiferromagnetic (AFM) after cooling in a zero magnetic field. The AFM state fully transforms into the FM state via a field-induced metamagnetic transition, and the critical field is ~HC = 34 kOe at 2 K. Another kind of metamagnetic transition is observed above the low-field TC, where a field-induced metamagnetic transition is between the paramagnetic (PM) and FM states. Both metamagnetic transitions are accompanied by large thermal and magnetic hystereses, and the Arrott plots confirm that the transitions are first order in nature. A large magnetocaloric effect in the La0.9Nd0.1Fe12B6 compound is observed in the vicinity of the field-induced PM-FM transition.