Self-magnetic compensation and shifted hysteresis loops in ferromagnetic samarium systems

Abstract

For Sm³⁺ ions in a vast majority of metallic systems, the following interesting scenario has been conjured up for long, namely, a magnetic lattice of tiny self- (spin-orbital) compensated 4f-moments exchange coupled (and phase reversed) to the polarization in the conduction band. We report here the identification of a self-compensation behavior in a variety of ferromagnetic Sm intermetallics via the fingerprint of a shift in the magnetic hysteresis (M-H) loop from the origin. Such an attribute, designated as exchange bias in the context of ferromagnetic/antiferromagnetic multilayers, accords these compounds a potential for niche applications in spintronics. We also present results on magnetic compensation behavior on small Gd doping (2.5 at. %) in one of the Sm ferromagnets (viz., SmCu₄Pd). The doped system responds like a pseudoferrimagnet and it displays a characteristic left-shifted linear M-H plot for an antiferromagnet.