Metal–insulator–metal transition in Ti substituted antiferromagentic Ru 2 MnGe Heusler alloy

We report the composition-induced metal-insulator crossover transition in Ti substituted Ru-based metallic full Heusler alloy Ru2MnGe where the both end of materials shows a metallic properties. The samples at the middle composition show the large negative magnetoresistance effect. The experimental results of the resistivity and the magnetization indicate that this metal-insulator transition is induced by the Kondo effect because Ti atoms on antiferromagnetic Ru2MnGe have an important role in appearance of insulator states. (C) 2012 Elsevier B.V. All rights reserved.