The thickness dependence of the magnetic properties of amorphous Fe90Zr10 layers has been explored using Fe90Zr10/Al75Zr25 multilayers. The Al75Zr25 layer thickness is kept at 40 \AA, while the thickness of the Fe90Zr10 layers is varied between 5 and 20 \AA. The thickness of the Al75Zr25 layers is sufficiently large to suppress any significant interlayer coupling. Both the Curie temperature and the spontaneous magnetization decrease non-linearly with decreasing thickness of the Fe90Zr10 layers. No ferromagnetic order is observed in the multilayer with 5 {\AA} Fe90Zr10 layers. The variation of the Curie temperature Tc with the Fe90Zr10 layer thickness t is fitted with a finite-size scaling formula [1−\Tc(t)/\Tc(∞)]=[(t−t′)/t0]−λ, yielding λ=1.2, and a critical thickness t′=6.5 \AA, below which the Curie temperature is zero.
@article{arxiv.1207.1327,
title = {Finite-size effects in amorphous Fe90Zr10/Al75Zr25 multilayers},
author = {P. T. Korelis and P. E. Jönsson and A. Liebig and H. -E. Wannberg and P. Nordblad and B. Hjörvarsson},
journal= {arXiv preprint arXiv:1207.1327},
year = {2012}
}