Revival of rhombohedral structure and complex magnetic response in (La, Cr) codoped BiFeO3

The polycrystalline ceramics of Bi0.83La0.17Fe1-xCrxO3 (BLFCO) have been synthesized by the solid-state reaction method to investigate the features of structural phase coexistence and complex magnetic response. The coexistence of the R3c rhombohedral and Pbam orthorhombic structures has been revealed by X-ray diffraction and Rietveld refinement. Selected-area Raman scattering spectra are used to further confirm a mixed phase state as both phonon vibrations of these phases are detectable. An unusual revival of the R3c phase is observed with increasing chromium concentration. The compound displays an intriguing weak magnetic response and some unique phenomena, such as the magnetic aging and field step-dependent hysteresis loop. The electric-field -controlled magnetism shows a complex behavior due to the interplay of the phase boundary ferromagnetism and structural phase transition.

Automated summary

Polycrystalline ceramics of Bi0.83La0.17Fe1-xCrxO3 (BLFCO) were synthesized using the solid-state reaction method to investigate the coexistence of different structural phases and complex magnetic response. X-ray diffraction and Rietveld refinement confirmed the coexistence of R3c rhombohedral and Pbam orthorhombic structures. Selected-area Raman scattering spectra further confirmed the mixed phase state. An unusual revival of the R3c phase was observed with increasing chromium concentration. The compound exhibited intriguing weak magnetic response and unique phenomena, such as magnetic aging and field step-dependent hysteresis loop. The electric-field-controlled magnetism displayed complex behavior due to the interplay between phase boundary ferromagnetism and structural phase transition.