Large Electro-Optic Effect in La-Doped 0.75Pb(Mg1/3Nb2/3)O3-0.25PbTiO3 Transparent Ceramic by Two-Stage Sintering

Highly transparent ceramics of La-doped 0.75Pb(Mg1/3Nb2/3)O-3-0.25PbTiO(3) were fabricated by a two-stage sintering method from conventional raw materials. The ceramics exhibited a transparency as high as 65% for the infrared wavelength. Large quadratic electro-optic coefficient of 66 x 10-16 (m/v)2 was obtained, which was the highest value reported so far in Pb(Mg1/3Nb2/3)O-3-PbTiO3 ceramics. The ferroelectric phase inducing the threshold electric field E-th and the domain structure of the transparent ceramics were studied.