Zero-field cooled exchange bias and magnetization reversal in La1.5Sr0.5Co0.4Fe0.6MnO6

The polycrystalline sample La1.5Sr0.5Co0.4Fe0.6MnO6 (LSCFMO) was prepared by sol-gel method and its magnetic properties were studied. The interesting magnetization reversal phenomenon and the zero-field cooled exchange bias (ZEB) effect were simultaneously observed in LSCFMO. ZEB effect can exist in a wider temperature range (0-200 K) compared with La1.5Sr0.5CoMnO6 (0-10 K), which is very important in the potential applications. A schematic diagram based on the coupling between the Fe3+ spins, Mn3+ spins and Co2+ or Co3+ spins is used to understand the ZEB and the reversal behaviors. Due to the doping of 60% Fe ion, the magnetic microstructure of LSCMFO is more complex than that of LSCMO, resulting in the meta-stable spin structure and more interesting magnetic phenomenon.