Features of the low-frequency polarization response in the region of the ferroelectric phase transition in multiferroic TbMnO$_{3}$

The unusual behavior of the low-frequency (10 Hz–1 MHz) permittivity in single crystals of ferroelectric multiferroic TbMnO$_{3}$ has been experimentally and theoretically studied in detail in the region of the narrow temperature peak of the permittivity, associated with the ferroelectric phase transition ($T_C$ $\sim$ 27.4 K). It has been found that the $\varepsilon'_{c}(\omega,T)$ maximum sharply decreases with increasing measured field frequency, while the temperature position of the maximum is independent of frequency. It has been shown that the observed features of the polarization response can be satisfactorily described within the Landau–Khalatnikov polarization relaxation theory.