5PbO·3GeO2 CRYSTAL; A NEW FERROELECTRIC

Abstract

Dielectric constants and refractive indices of a 5PbO · 3GeO₂ crystal, which was grown from the melt by by the Czochralski method, were measured as a function of temperature. The crystal was identified as a new type of ferroelectric with spontaneous polarization P_s = 0.046 C/m², coercive field E_c ∼ 2.3 × 10⁶ V/m at room temperature, and T_c = 177°C.