English

Griffiths-like phase, spin-phonon coupling, and exchange-bias in the disordered double perovskite GdSrCoMnO$_{6}$

Materials Science 2026-04-23 v1

Abstract

We report structural, magnetic, and Raman studies of the disordered double perovskite GdSrCoMnO6_{6}~(GSCM). DC magnetization shows a ferromagnetic transition at TC153T_{C} \approx 153~K. The inverse susceptibility exhibits a downturn above TCT_{C} and is consistent with a Griffiths-like regime extending up to TG172T_{G} \approx 172~K. Raman measurements show a deviation of the phonon frequency from the anharmonic background near the magnetic-ordering region, consistent with spin-phonon coupling. AC susceptibility indicates slow magnetic dynamics below the freezing temperature Tf30T_{f} \approx 30~K. These results point to magnetic inhomogeneity generated by the random distribution of mixed-valence Co and Mn ions and by the resulting competition between ferromagnetic and antiferromagnetic interactions. In the low-temperature regime, an exchange-bias effect is observed up to 50~K, with an exchange-bias magnitude HEB=379|H_{EB}| = 379~Oe at 5~K. Structural disorder therefore plays an important role in the magnetic correlations, spin dynamics, and spin-lattice response of GSCM.

Keywords

Cite

@article{arxiv.2604.19894,
  title  = {Griffiths-like phase, spin-phonon coupling, and exchange-bias in the disordered double perovskite GdSrCoMnO$_{6}$},
  author = {Gyanti Prakash Moharana and Diptikanta Swain and Hanuma Kumar Dara and Debendra Prasad Panda and S. N Sarangi},
  journal= {arXiv preprint arXiv:2604.19894},
  year   = {2026}
}

Comments

13 pages, 10 figures