Accession Number : AD0267433

Title :   NONLINEAR MICROWAVE DIELECTRIC MATERIALS

Corporate Author : RAYTHEON CO WALTHAM MA

Personal Author(s) : RUPPRECHT, G. ; SILVERMAN, B.D.

Report Date : 15 JUN 1961

Pagination or Media Count : 1

Abstract : The study of the applicability of materials with nonlinear dielectric properties to microwave devices was made. To facilitate this study it was necessary to understand the theoretical origin of the microwave losses and nonlinear dielectric constant. Studies were made on both single crystalline and polycrystalline barium-strontium titanates at 1000 cps and microwave frequencies. Barium-strontium titanate crystals with a high concentration of barium titanate were grown from a flux. Measurement of the Curie temperature by observing the dielectric constant at 1000 cps was made. The microwave losses of these mixtures are quite high. The crystals on which the measurements were made were relatively imperfect. Oxygen deficient strontium titanate exhibits an ionic conductivity that contributes to the microwave losses at high temperatures, but does not affect the low temperature losses. A microwave phase shifter has been constructed using BST-50, which exhibits a phase shift of up to 340 degrees, but has a real loss of around 20 db. (Author)

Descriptors :   *BARIUM COMPOUNDS, *DIELECTRICS, *PHASE SHIFT CIRCUITS, *STRONTIUM COMPOUNDS, *TITANATES, CRYSTALS, DIELECTRIC PROPERTIES, ELECTRICAL CONDUCTIVITY, FREQUENCY, GROWTH(PHYSIOLOGY), HEAT TREATMENT, MATERIALS, MEASUREMENT, MICROWAVE EQUIPMENT, RESONANCE, SINGLE CRYSTALS.

Distribution Statement : APPROVED FOR PUBLIC RELEASE