Scaling behavior of dynamic hysteresis in Na0.5Bi4.5Ti4O15 bulk ceramics

The ferroelectric hysteresis loops of sodium bismuth titanate Na0.5Bi4.5Ti4O15 bulk ceramics were measured under periodical electric field in range of frequency from 0.01Hz to 100Hz and field from 10kV/cm to 150kV/cm. The three-stage scaling behavior of dynamic hysteresis was investigated in Na0.5Bi4.5Ti4O15 bulk ceramics. The scaling behavior at low amplitude of electric field is described as is proportional to f^(-0.122)E0^3.30 for low frequency and is proportional to f^(-0.122)E0^3.15 for high frequency. , f and E0 represent the area of hysteresis loop, frequency and amplitude of periodic electric field, respectively. At E0 around coercive field, scaling behavior takes the form of is proportional to f^(-0.11)E0^4.28 for low frequency and is proportional to f^(-0.11)E0^4.17 for high frequency. At high E0, we obtained is proportional to f^(-0.04)E0^2.90 for low frequency and is proportional to f^(-0.06)E0^2.75 for high frequency. The contribution to scaling relation mainly results from reversible of ferroelectric domain switching at low E0, the velocity of domain wall motion at E0 around coercive field and simultaneously reversible and irreversible domain switching at high E0.
Comment: 8 pages, 3 figures