Effect of Hydrostatic Pressure on the Antiferroelectric Phase Transitions in Ammonium Dihydrogen Arsenate NH₄H₂AsO₄ and Deuterated Analogue

Abstract

Effect of hydrostatic pressure on the antiferroelectric phase transitions in NH₄H₂AsO₄ and deuterated analogue (deuterium concentration ∼80%) was studied by dielectric constant measurements at high pressures up to about 0.8 GPa. The transition temperature linearly decreases with increasing pressure with the ratios of −19.7 K GPa⁻¹ and −14.5 K GPa⁻¹ for NH₄H₂AsO₄ and the deuterated compound, respectively. The pressure effect is compared with previously reported results of other KH₂PO₄-type ferro- and antiferroelectric crystals.