Magnetic field and pressure effects on the magnetic transitions of La0.9Ca0.1MnO3 perovskites - art. no. 054436

摘要

The stability under pressure and magnetic field of the different magnetic phases of La0.9Ca0.1MnO3 perovskite has been studied. This is accomplished by monitoring the pressure-induced shift in temperature of the two peaks that appear in the real part of the ac susceptibility, chi'(T), corresponding to the transition into the ferromagnetic (F) phase at T-F and then into the canted antiferromagnetic (AF) phase at T-AF. It is found that both T-F and T-AF shift up in temperature indicating the reinforcement of both F and AF interactions under pressure. The magnetic field favors parallel alignments of spins and, therefore, in the presence of a magnetic field the F phase expands at the expense of both canted AF and paramagnetic phases. On the other hand the observed thermal hysteresis and the frequency dependence of the ac susceptibility clearly indicate the existence of a nonhomogeneous magnetic state below T-F, in agreement with neutron-diffraction results. [References: 21]