Dielectric relaxations, magnetodielectric and magnetoelectric interactions in Bi$_{0.6}$La$_{0.4}$MnO$_{3}$ ceramics

Complex permittivity $\varepsilon^{*}/\varepsilon_{0} =\varepsilon'/\varepsilon_{0}-i\varepsilon''/\varepsilon_{0}$ of the bismuth–lanthanum manganite Bi$_{0.6}$La$_{0.4}$MnO$_{3}$ ceramics has been measured in the temperature range of 10–220 K at frequencies $f$ = 20–106 Hz and magnetic inductions $B$ = 0–0.846 T. At a temperature of 80 K, the spectra $\varepsilon'/\varepsilon_{0}(f)$ and $\varepsilon''/\varepsilon_{0}(f)$ demonstrate the dielectric relaxation that is a superposition of contributions of several relaxation processes, each of which is dominant in its frequency range: I($f<$ 10$^{3}$ Hz), II(10$^{3}$ $< f<$ 10$^{5}$ Hz), and III(10$^{5}$ $<f<$ 10$^{6}$ Hz). In the range of 10–120 K, anomalous behavior of $\varepsilon'/\varepsilon_{0}(T)$ and $\varepsilon''/\varepsilon_{0}(T)$ is observed near the temperature of the transition from the paramagnetic to ferromagnetic phase and is due to the Anderson localization of charge carrier on a spin disorder.