Neel temperature of Cr2O3 in Cr2O3/Co exchange-coupled system: Effect of buffer layer

The lattice parameter dependence of the Neel temperature T-N of thin Cr2O3 in a Cr2O3/Co exchange-coupled system is investigated. Lattice-mismatch-induced strain is generated in Cr2O3 by using different buffer layers. The lattice parameters are determined from out-of-plane and in-plane X-ray diffraction measurements. The Neel temperature is detected by direct temperature-dependent magnetization measurement as well as the temperature-dependent interface exchange coupling energy. It is observed that in-plane lattice contraction can enhance T-N in Cr2O3, which is consistent with theoretical calculations. (c) 2015 AIP Publishing LLC.