Positive exchange bias from magnetization reversal in La1−xPrxCrO3 (x ∼ 0.7–0.85)

The perovskite chromite La1−xPrxCrO3 shows an unusual positive exchange bias (PEB) and a negative exchange bias (NEB) associated with magnetization reversal, arising from an antiparallel Pr3+-Cr3+ coupling. Below ∼200 K, changing the cooling magnetic field switches the type of EB. A PEB appears in low cooling fields (<3–15 kOe), comparable with the internal magnetic field at the Pr site. The appearance of PEB or NEB depends on the orientation of the Pr3+ moment with respect to the canted Cr3+ component.