Dielectric, electromechanical, and elastic properties of Rb1–x(NH4)xH2PO4 single crystals

Аннотация

The longitudinal dielectric, piezoelectric, and elastic characteristics of ferroelectric RbH₂PO₄ and antiferroelectric NH₄H₂PO₄ crystals are calculated in terms of the modified model of proton ordering with allowance for the piezoelectric coupling in an approximation of a four-particle cluster. The results obtained agree well with known experimental data. Along with this, the electromechanical properties of a Rb_0.2(NH₄)_0.8H₂PO₄ single crystal undergoing an antiferroelectric phase transition have been studied experimentally over a wide temperature range. The model predictions and the experimental data agree qualitatively.