engleski

Competing antiferromagnetism and local magnetic order in the bulk ceramic PZT–PFW multiferroic system: searching for the most promising ratio between PZT and PFW

Bulk ceramic compounds of formula xPZT+(1−x)PFW, where PZT = Pb(Zr0.575Ti0.425)O3 and PFW = Pb(Fe2/3W1/3)O3, for x = 0.15 ; 0.20 ; 0.25 ; 0.37 ; 0.50 ; 0.60 ; 0.65 ; 0.70 and 0.80, were synthesized. In these single phase perovskites a change from rhombohedral to cubic structure is observed as the proportion of PFW increases. Magnetic investigations including zero-field cooled and field-cooled magnetization versus temperature measurements, magnetic hysteresis loops measurement and ac susceptibility measurements were performed. At high temperatures a clear antiferromagnetic (AFM)-like transition was observed for high PFW concentrations. The low temperature behaviour indicated spin freezing and thermal activation of magnetic moments and measurements confirmed the existence of a barrier maximum for x = 0.37. Competition between the long-range AFM order and short-range magnetic ordering of small nano-sized regions with finite magnetic moments was observed in the studied system.

magnetic ceramics; perovskites; magnetic nano-regions; multiferroics; slow magnetic dynamics; thermal activation

nije evidentirano