Research Update: Magnetic phase diagram of EuTi1−xBxO3 (B = Zr, Nb)

We report the magnetic phase diagram of EuTi1−xBxO3 (B = Zr, Nb), determined from magnetization and heat capacity measurements. Upon Zr-doping, the antiferromagnetic ordering temperature TN of EuTi1−xZrxO3 gradually decreases from 5.6 K (x = 0) to 4.1 K (x = 1). Whereas a similar decrease in TN is observed for small amounts of Nb doping (x ≤ 0.05), ferromagnetism is induced in EuTi1−xNbxO3 with x > 0.05. The ferromagnetic interaction between localized Eu 4f spins mediated by itinerant electrons introduced by Nb doping results in the ferromagnetism in EuTi1−xNbxO3.