Finite-Size Effects and Uncompensated Magnetization in Thin Antiferromagnetic CoO Layers

Finite-size effects in CoO, an antiferromagnetic insulator with localized moments, have been observed in CoO/Si${\mathrm{O}}_2$ multilayers. The Néel temperatures of the CoO layers, as determined by dc susceptibility measurements, show a finite-size scaling relation with a shift exponent $\lambda =1.55\mathrm{}\pm 0.05$. Increased magnetization with an oscillation in magnitude, due to uncompensated antiferromagnetic layers, has also been observed.