Structural and electrical transport properties were investigated for Heusler-type alloy Ru 2 MnGe thin films. Ru 2 MnGe films on MgO substrate were subjected to an in-plane compressive strain due to their small lattice mismatch (-0.7\%, and exhibited enhanced antiferromagnetic transition temperature (T-N up to 353 K, which is much higher than that of the bulk material (T-N= 316 K). In contrast, the films on MgAl 2O 4 were almost in a relaxed-strain state, and showed T N close to the bulk value (304 K). It was also found that the T N of Ru 2MnGe thin films on MgO exhibited oscillating behavior depending on c/a ratio. We argued that the next-nearest neighbor magnetic interactions (J-2 of Mn-Mn atoms has oscillated depending on the degree of strain in Ru 2MnGe, which contribute to the oscillating behavior of T N against c/a.
ASJC Scopus subject areas