Dynamics of magnetic inhomogeneity in La2CoMnO6 films probed by Raman spectroscopy
A V S Silva1, R X Silva2, C W A Paschoal3
1Instituto Federal do Rio Grande do Norte, Campus Pau dos Ferros, Pau dos Ferros, Rio Grande do Norte 59900-000, Brazil; Departamento de Física, Universidade Federal do Ceará, PO BOX 6030, Campus do Pici, Fortaleza, Ceará 65455-900, Brazil.
Abstract:
We report the dynamic effects of magnetic inhomogeneity on the temperature evolution of the Raman modes in polycrystalline La2CoMnO6 (LCMO) films. The LCMO films were obtained via chemical solution deposition and annealed at different temperatures, 700, 800 and 900 °C. Temperature-dependent Raman spectroscopic studies uncover anomalous phonon energy behaviors, associated with strong spin-phonon couplings revealed even at ambient conditions. This effect, which is observed to occur well above ferromagnetic ordering temperature is ascribed to short-range Mn4+/Co2+ ferromagnetic clusters. Moreover, our study has shown that spin-phonon coupling strength is governed by competing antiferromagnetic (AFM) and ferromagnetic (FM) interactions. These results significantly enhance the understanding of the complex spin-phonon coupling mechanism to provide insights into magnetic inhomogeneity in systems with two or more magnetic sublattices. These findings suggest the presence of similar effects in other double perovskites within the RE2CoMnO6 (RE = rare earths) family, which exhibit analogous magnetic sublattice and order-disorder defects.
Related Concept Videos
Raman Spectroscopy: Overview
However, a small fraction of the scattered light exhibits a frequency shift due to the exchange of energy between the incident photons and...
Raman Spectroscopy Instrumentation: Overview
The monochromatic laser source, typically using visible or near-infrared radiation, generates a highly focused beam of light. This light interacts with the molecules of the sample, scattering some of the light. Liquid and gaseous samples are usually tested in ordinary glass capillaries, while solids can be analyzed as powders packed in capillaries or as potassium...
Atomic Nuclei: Magnetic Resonance
NMR Spectroscopy: Spin–Spin Coupling
NMR Spectrometers: Resolution and Error Correction
Ferromagnetism


