Weak antiferromagnetic (AF) interaction in the ferromagnetic (FM) partially ordered La2CoMnO6 (LCMO) was detected by Raman spectroscopy by monitoring spin-phonon coupling. Because of the sensibility to probe short-range disorder and lattice modifications, the Raman spectroscopy showed to be an useful tool to indicate less remarkable magnetic transitions in LCMO compound. Apart from the expected spin-phonon coupling due to the long-range FM superexchange (Tc~230 K), phonons parameters pointed out an additional spin-phonon coupling related to the short-range AF interaction at Tc~135 K, which was not detected from the magnetic bulk response. These results reinforce the Raman spectroscopy as a powerful technique to detect antisite disorder into A2B'B"O6 magnetic double perovskites, whose magnetic properties are driven by superexchange interactions.
@article{arxiv.1802.07326,
title = {Short-range antiferromagnetic interaction and spin-phonon coupling in La2CoMnO6 double perovskite},
author = {R. X. Silva and C. C. Santos and H. Reichlova and X. Marti and R. Paniago and C. W. A. Paschoal},
journal= {arXiv preprint arXiv:1802.07326},
year = {2022}
}