Giant zero field cooled spontaneous exchange bias effect in phase separated La1.5Sr0.5CoMnO6

We report a giant zero field cooled exchange bias (ZEB) effect (similar to 0.65 T) in La1.5Sr0.5CoMnO6 sample. Magnetic study has revealed a reentrant spin glass similar to 90 K, phase separation to spin glass and ferromagnetic phases below 50K and canted antiferromagnetic transition similar to 10K. A small conventional exchange bias (CEB) is established with the advent of spontaneous phase separation down to 10K. Giant ZEB and enhanced CEB effects are found only below 10K and are attributed to the large unidirectional anisotropy at the interface of isothermally field induced ferromagnetic phase and canted antiferromagnetic background. (C) 2013 AIP Publishing LLC.