Magnetic control of the zero-magnetization ferromagnet Sm1−xGdxAl2

X-ray magnetic circular dichroism experiments have been performed up to \ifmmode\pm\else\textpm\fi{}17 T to investigate the magnetic configuration and magnetization reversal of an original zero-magnetization ferromagnet Sm${}_{1\ensuremath{-}x}$Gd${}_{x}$Al${}_{2}$ ($x$ $=$ 0.028), both as a single epitaxial layer and as a pinning layer in an exchange-coupled system. The Sm${}_{0.972}$Gd${}_{0.028}$Al${}_{2}$ single layer appears to exhibit an extraordinary large coercivity that exceeds 20 T below its magnetic compensation (${T}_{\mathrm{comp}}$). Despite such huge magnetic stability in the single layer, interface exchange coupling in the bilayer drives the formation of domains in Sm${}_{0.972}$Gd${}_{0.028}$Al${}_{2}$ and their reversal upon field, both below and at magnetic compensation. Increasing the cooling field yields the increase in exchange-favored domains in Sm${}_{0.972}$Gd${}_{0.028}$Al${}_{2}$, surprisingly also at ${T}_{\mathrm{comp}}$, whereas, Zeeman energy does not favor this specific orientation neither at compensation nor during the cooling process. We propose a possible scenario for those domains' formation and highlight the way the external magnetic field may tune the magnetic configuration in such a zero-magnetization ferromagnet. The cooling field also consequently influences the SmAl${}_{2}$ magnetization reversal which is biased by pinned magnetic components in Sm${}_{0.972}$Gd${}_{0.028}$Al${}_{2}$; the bias field is satisfactorily explained in considering different pinned contributions with opposite magnetic orientations.