Investigating the dielectric properties of potassium iodate polycrystals
Linear and nonlinear dielectric properties of KIO3 polycrystalline samples are investigated. It is shown that linear dielectric permittivity ε' displays four anomalies corresponding to phase transitions in KIO3. Anomalies of third-harmonic coefficient γ3ω are observed at temperatures of 113, 263, and 345 K, corresponding to phase transitions between KIO3 ferroelectric phases. It is established that the third-harmonic coefficient responsible for the nonlinearity of dielectric properties displays no anomalies during the transition to the paraelectric phase of KIO3 at approximately 485 K. Possible reasons for there being no such anomaly are discussed.