Multiferroic properties and magnetoelectric coupling in highly textured Pb(Fe0.5Nb0.5)O3 thin films obtained by RF sputtering

The ferroelectric and magnetic properties and the magnetoelectric coupling (MEC) effects of Pb(Fe0.5Nb0.5)O3 (PFN) thin films grown on SrRuO3/Si substrates by the radiofrequency (RF) magnetron sputtering technique were studied. Highly textured, single-phase films with [1 1 0] preferential orientation and different thicknesses were successfully grown. Electric (P–E) hysteresis loops showed excellent and almost constant values of the maximum (∼65 μC cm−2) and remanent (∼25 μC cm−2) polarizations from 4 K to room temperature. Ferromagnetic order in the low-temperature region (below 50 K) is reported for the first time in PFN and discussed. The maximum (∼3 emu g−1) and remanent (∼1.5 emu g−1) magnetization values were obtained. Magnetic field dependence of the ferroelectric hysteresis loops was investigated for temperatures of between 4 and 100 K. Coexistence of ferroelectricity, magnetism and spin crossover phenomena were observed, and a significant direct DC MEC effect expressed by the coefficient α = ΔPr/ΔH with maximum value of 120 pC cm−2 Oe−1 at 4 K is reported.