Griffiths phase and spontaneous exchange bias in La$_{1.5}$Sr$_{0.5}$CoMn$_{0.5}$Fe$_{0.5}$O$_{6}$

A. G. Silva; K. L. Salcedo Rodríguez; C. P. Contreras Medrano; G. S. G. Lourenço; M. Boldrin; E. Baggio-Saitovitch; L. Bufaiçal

doi:10.1088/1361-648x/abc595

arXiv · 2010.11110

Griffiths phase and spontaneous exchange bias in La$_{1.5}$Sr$_{0.5}$CoMn$_{0.5}$Fe$_{0.5}$O$_{6}$

A. G. Silva·K. L. Salcedo Rodríguez·C. P. Contreras Medrano·G. S. G. Lourenço·M. Boldrin·E. Baggio-Saitovitch·L. Bufaiçal

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Abstract

La$_{1.5}$Sr$_{0.5}$CoMn$_{0.5}$Fe$_{0.5}$O$_{6}$ (LSCMFO) compound was prepared by solid state reaction and its structural, electronic and magnetic properties were investigated. The material forms in rhombohedral $R\bar{3}c$ structure, and the presence of distinct magnetic interactions leads to the formation of a Griffiths phase above its FM transition temperature (150 K), possibly related to the nucleation of small short-ranged ferromagnetic clusters. At low temperatures, a spin glass-like phase emerges and the system exhibits both the conventional and the spontaneous exchange bias (EB) effects. These results resemble those reported for La$_{1.5}$Sr$_{0.5}$CoMnO$_{6}$ but are discrepant to those found when Fe partially substitutes Co in La$_{1.5}$Sr$_{0.5}$(Co$_{1-x}$Fe$_{x}$)MnO$_{6}$, for which the EB effect is observed in a much broader temperature range. The unidirectional anisotropy observed for LSCMFO is discussed and compared with those of resembling double-perovskite compounds, being plausibly explained in terms of its structural and electronic properties.

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A. G. Silva, K. L. Salcedo Rodríguez, C. P. Contreras Medrano, G. S. G. Lourenço, M. Boldrin, E. Baggio-Saitovitch, L. Bufaiçal. 2020-10-21. Griffiths phase and spontaneous exchange bias in La$_{1.5}$Sr$_{0.5}$CoMn$_{0.5}$Fe$_{0.5}$O$_{6}$. https://doi.org/10.1088/1361-648x/abc595

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