Giant exchange bias field above room temperature in perovskite YbCr 1- x Fe x O 3 ( x = 0.6-0.9).

Temperature-induced exchange bias is observed in perovskite YbCr 1- x Fe x O 3 ( x = 0.6-0.9) compounds. This is ascribed to the ferromagnetic (FM) coupling between Fe 3+ /Cr 3+ ions and Yb 3+ ions. During demagnetization, the Yb 3+ ions will show a tendency to rotate with the direction of the applied magnetic field. However, the antiferromagnetic coupling of Fe 3+ /Cr 3+ ions has a pinning effect, hindering their rotation, and thus producing an exchange bias effect. With increasing Fe 3+ ion content, the magnetization and exchange bias field gradually become larger. When x = 0.8 and 0.9, the exchange bias field reaches up to -9.7 kOe and -13.6 kOe at 300 K, respectively. This giant room temperature exchange bias field will be more conducive for practical applications in magnetoelectronic devices.