Fabrication of Transparent Tellurite Glasses Containing Potassium Niobate Crystals by an Incorporation Method

To fabricate transparent oxide glasses containing ferroelectric KNbO3 crystals, a new method in which KNbO3 particles are directly incorporated into TeO2─K2O─Nb2O5 glasses has been developed. Transparent TeO2-based glasses containing KNbO3 crystals with a diameter of ∼ 10 μm have been first successfully fabricated by adjusting temperature and time for incorporation. A small difference in the refractive indexes, n, between TeO2-based matrix glasses (n= 2.0) and incorporated KNbO3 crystals (n= 2.21) is a significant reason for the transparency. This new method is applicable for the fabrication of new transparent glasses containing other functional materials with high refractive indexes.