Ferroelectric phase transitions: A review of theory and experiment

Non-Debye domain wall response in KH 2 PO 4

“…Though Debye behavior results from quite different models treating dielectric domain wall contributions [2,5,[17][18][19][20], there is little understanding about the nature of the underlying mechanism in KH 2 PO 4 , its nonlinearity and the influence of temperature and impurity concentration. The dielectric function * (f ) describing the low-frequency dispersion is not reported yet.…”

“…Monodispersive relaxation, being a phenomenon rarely observed in solids, is a rather unexpected result in KH 2 PO 4 as far as the dielectric response of an irregular domain structure is concerned. The domain wall response in ferroelectrics has been extensively discussed in terms of models [17][18][19] treating field induced shifts of the infinitely stiff domain wall as a whole. Debye-type spectra were obtained theoretically with relaxation times depending on the restoring and frictional forces acting on the oscillating wall.…”