Oscillatory exchange bias and training effects in nanocrystalline Pr0.5Ca0.5MnO3
S. Narayana Jammalamadaka,
S. S. Rao,
S. V. Bhat,
J. Vanacken,
V. V. Moshchalkov
Affiliations
S. Narayana Jammalamadaka
INPAC – Institute for Nanoscale Physics and Chemistry, Nanoscale Superconductivity and Magnetism and Pulsed Fields Group, K.U. Leuven, Celestijnenlaan 200D, B–3001 Leuven, Belgium
S. S. Rao
INPAC – Institute for Nanoscale Physics and Chemistry, Semiconductor Physics Laboratory, K.U. Leuven, Celestijnenlaan 200D, B–3001 Leuven, Belgium
S. V. Bhat
Department of Physics, Indian Institute of Science, Bangalore – 560012, India
J. Vanacken
INPAC – Institute for Nanoscale Physics and Chemistry, Nanoscale Superconductivity and Magnetism and Pulsed Fields Group, K.U. Leuven, Celestijnenlaan 200D, B–3001 Leuven, Belgium
V. V. Moshchalkov
INPAC – Institute for Nanoscale Physics and Chemistry, Nanoscale Superconductivity and Magnetism and Pulsed Fields Group, K.U. Leuven, Celestijnenlaan 200D, B–3001 Leuven, Belgium
We report on exchange bias effects in 10 nm particles of Pr0.5Ca0.5MnO3 which appear as a result of competing interactions between the ferromagnetic (FM)/anti-ferromagnetic (AFM) phases. The fascinating new observation is the demonstration of the temperature dependence of oscillatory exchange bias (OEB) and is tunable as a function of cooling field strength below the SG phase, may be attributable to the presence of charge/spin density wave (CDW/SDW) in the AFM core of PCMO10. The pronounced training effect is noticed at 5 K from the variation of the EB field as a function of number of field cycles (n) upon the field cooling (FC) process. For n > 1, power-law behavior describes the experimental data well; however, the breakdown of spin configuration model is noticed at n ≥ 1.
