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

Abstract

For ${\text{Sm}}^{3+}$ 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 $(M\text{\ensuremath{-}}H)$ 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 $(2.5\text{ }\text{at}\text{.}\text{ }\mathrm{%})$ in one of the Sm ferromagnets (viz., ${\text{SmCu}}_{4}\text{Pd}$). The doped system responds like a pseudoferrimagnet and it displays a characteristic left-shifted linear $M\text{\ensuremath{-}}H$ plot for an antiferromagnet.