How to obtain magnetocapacitance effects at room temperature: The case of Mn-doped BiFeO3

Phase transition and enhanced magneto-dielectric response in BiFeO3-DyMnO3 multiferroics

“…35,37 Moreover, AFM-T N decreases monotonically with increase in x, as evident from Fig. 6(a) 20 suggests that a strong antiferromagnetic interaction is probable between the Fe ions and a ferromagnetic interaction appear between the vacant Mn 3þ orbital and filled Fe 3þ orbital in perovskites. This breakdown the balance between the antiparallel sublattice magnetization of Fe 3þ , due to metal-ion substitution with a different valence.…”

“…Asymptotically, a decrease in T N toward room temperature could be accomplished by substitution of Mn 3þ ions at the Fe 3þ -site of BFO. 9,20 It has also been reported that dielectric losses, resistivity, and magnetic properties of BFO can be significantly enhanced by substitution of Mn 3þ ion at the Fe 3þ site. 13 Chemical substitution of RE cation at the Bi-site of BFO has been established to be an effective approach to stabilize the perovskite phase and reduce the leakage current with improved multiferroic properties.…”

Piezoresponse force microscopy investigations of Aurivillius phase thin films

“…[7][8][9][10][11][12][13][14][15] Chemical doping of perovskite type materials, without producing a large decrease in their Curie temperature ͑T c ͒, has been useful in enhancing their electrical and magnetic properties. 9,[16][17][18][19][20] Mn 3+ doping has been reported to be effective for suppressing leakage current and improving the polarization switching properties of Bi 4 Ti 3 O 12 single crystals. 19 Other workers 9,21 have found that electrical conductivity in Bi 5 Ti 3 Fe 1−x Mn x O 15 ͑x =0-1͒ ceramics increases with x.…”

“…The Curie temperature was shifted toward the low temperature region at x Ն 0.4. Based on the idea that magnetoelectric coupling could be amplified near a transition temperature 22,23 and that ferromagnetic interactions should appear between the vacant Mn 3+ eg orbital and the filled Fe 3+ eg orbital in a perovskite structure, 24 Yang et al 20 attempted to bring the Piezoreponse force microscopy ͑PFM͒ has emerged as a powerful technique for probing nanoscale phenomena in piezoelectric and ferroelectric materials on the nanometer and micrometer scales. [25][26][27][28][29][30][31][32][33][34] PFM is based on the detection of a bias-induced piezoelectric surface deformation.…”

High-temperature phases of multiferroic BiFe0.7Mn0.3O3

“…Many dopants have been used to modify or stabilise the properties of BiFeO 3 and also to try to gain insight into the underlying physics of the undoped parent compound [5][6][7] . Substitution of Mn 3+ for Fe 3+ increases the magnetization and dielectric constant although T N and T C are lower than in the pure compound 5,8,9 . The Mn-substituted compound BiFe 0.7 Mn 0.3 O 3 has been reported, based upon x-ray diffraction, differential thermal analysis (DTA), dilatometry and conductivity data, to have lower transition temperatures than the parent compound: T α−β =943 K and T β−γ =1160 K, with peritectic decomposition reported at 1193 K 10,11 .…”