Spin phonon coupling and magneto-dielectric coupling in BiFeO3–TbMnO3 composite. (14th June 2019)

• Record Type: Journal Article
• Authors: Gupta, Prince K; Ghosh, Surajit; Kumari, Seema; Pal, Arkadeb; Roy, Somnath; Singh, Rahul; Singh, Prajyoti; Singh, Ranjan K; Ghosh, A K; Chatterjee, Sandip
• Is Part Of: Materials research express. Volume 6:Number 8(2019)
• Publication Date: 2019-06-14
• Subjects: bismuth ferrite -- spin phonon coupling -- magnetodilectric coupling -- TbMnO3 -- composite; Materials science -- Research -- Periodicals; Materials science -- Periodicals; 620.11
• DOI: 10.1088/2053-1591/ab2742
• Languages: English
• ISSNs: 2053-1591

Abstract

Abstract: Magneto-structural and magneto-electric coupling in multiferroic composite BiFeO3 –TbMnO3 have been investigated. Anomalous softening of the phonon modes was observed ∼210 K (close to the spin reorientation transition temperature T*) in the temperature dependent Raman spectra which might be a result of spin phonon coupling in the lattice. Relaxor type ferroelectric behaviour was observed in the temperature dependent dielectric measurements where the relaxation was found near T*. The frequency dependent dielectric study and the impedance spectroscopy revealed that the dielectric properties are a mixture of intrinsic Debye relaxation and Maxwell-Wagner relaxation arising from the space charge polarization at the interface of the composite. A large positive magneto-dielectric (MD) coupling was found near the relaxation temperature which is understood to be originated as a result of the magneto-structural coupling in the system.