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Photocurrents in doped LiNbO3 crystals are shown to be due to a bulk photovoltaic effect with saturation voltages in excess of 1000 V (∼105 V/cm). This effect accounts for the light-induced index changes in LiNbO3. An explanation of the photovoltaic effect, based on the asymmetry of the lattice, is proposed.

The dielectric constants, electrical conductivity, specific heat, and pyroelectric coefficients of ferro-electric Sr1−xBaxNb2O6 (SBN) are investigated as a function of temperature in the range 10°–500°K, and as a function of the Sr/Ba composition of the material. A simple technique for measuring absolute pyroelectric coefficients and spontaneous polarizations of ferroelectrics is described. The electric field and frequency dependence of the dielectric properties are also investigated. The theory of pyroelectric detection is discussed from a materials point of view, and the experimental data are considered in terms of the usefulness of SBN as a pyroelectric detector of electromagnetic radiation.

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Alkali niobate and tantalate glasses have been prepared by rapid quenching. These glasses exhibit room-temperature ionic conductivities as high as 10−5 (Ω cm)−1 and electronic conductivities less than 10−11(Ω cm)−1. In the case of LiNbO3, the glass conductivity is many orders of magnitude greater than that of the single crystal. These conductivities are sufficiently high for rapidly quenched vitreous oxides to be considered for applications as solid electrolytes.

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