  Synthesizing half-metallic fully-compensated ferrimagnets that form in the
inverse Heusler phase could lead to superior spintronic devices. These
materials would have high spin polarization at room temperature with very
little fringing magnetic fields. Previous theoretical studies indicated that
Cr2CoAl should form in a stable inverse Heusler lattice due to its low
activation energy. Here, stoichiometric Cr2CoAl samples were arc-melted and
annealed at varying temperatures, followed by studies of their structural and
magnetic properties. High-resolution synchrotron X-ray diffraction revealed a
chemically ordered Heusler phase in addition to CoAl and Cr phases. Soft X-ray
magnetic circular dichroism revealed that the Cr and Co magnetic moments are
antiferromagnetically oriented leading to the observed low magnetic moment in
Cr2CoAl.
