Emergence of exchange bias effect in double perovskite La2Cu0.9Fe0.1IrO6 originated from Fe doping

Abstract

The effect of partial electron doping (10% Fe) in the antiferromagnetic (AFM) double perovskite La2CuIrO6 (LCO) has been investigated at the macroscopic level using X-ray diffraction (XRD), and DC Magnetic measurements to study the evolution of complex magnetic order. The experimental observations indicate a significant modification in the nature of microscopic magnetic interaction induced by charge imbalance resulting in strong ferromagnetic (FM) ordering in the parent antiferromagnetic LCO. The nature of magnetic interaction results in a cluster-glass state (CG) with novel zero-field-cooled exchange bias (ZEB) and conventional exchange bias (CEB) effect at low temperature. Obtained ZEB field value is 0.735 kOe at 3 K, while an unusually large CEB field of 9.24 kOe for a bias cooling field (HB) of 50 kOe has been observed at the same temperature. The doped LCO also shows the training effect in field cooled M(H) measurements, following the frozen spin relaxation behavior, indicating the cluster-glass (CG) nestle in the interface/pinning boundary. The emerged complex exchange interaction among different magnetic ordering, i.e., FM, AFM, and CG, significantly influences the CEB as well as ZEB.