Effect of Mn-doping on the low temperature magnetic phase transitions of BiFeO3

摘要: Abstract In the present work, we have carried out a comparative study of low temperature phase transitions using dc magnetization (M (T)) and ac susceptibility (χ (ω, T)) measurements on undoped 0.3 wt% MnO2 doped BiFeO3 samples in 2–300 K range. It is shown that doping increases resistivity decreases dielectric loss as result reduced oxygen vacancy concentration confirmed by iodometry x-ray photoelectron spectroscopy (XPS) studies. A M (T) χ T) results two types reveal around 25 K, 110 to 150 K 260 K are intrinsic BiFeO3. The widely reported transition at 50 K argued be defect induced, it absent samples. We also show spin-glass (TSG) ∼20 K, determined from an analysis T), less than freezing (Tf) ∼25 K marked contrast TSG > Tf earlier workers.