Whispering-gallery mode technique applied to the measurement of the dielectric properties of Langasite between 4 K and 300 K

Author

Giordano, Vincent ; Hartnett, John G. ; Krupka, Jerzy ; Kersalé, Yann ; Bourgeois, Pierre-Yves ; Tobar, Michael E.

Author_Institution

Lab. de Phys. et Metrol. des Oscillateurs, CNRS, Besancon, France

Volume

51

Issue

5

fYear

2004

fDate

5/1/2004 12:00:00 AM

Firstpage

484

Lastpage

490

Abstract

We report new measurements of dielectric properties of Lanthanum gallium silicate (Langasite or LGS) conducted with the whispering-gallery mode technique at microwave frequencies and between 4.2 K and 300 K. The real part of the permittivity tensor of LGS presents two components having temperature coefficients of opposite sign. This unique property enables the design of a temperature compensated resonator that may be useful in building stable microwave oscillators or filters. We report also the first measurements of the two independent components of the imaginary part of the permittivity tensor. It appears LGS is a relatively high-loss dielectric material compared with sapphire or quartz.

Keywords

dielectric resonators; gallium compounds; lanthanum compounds; permittivity; 4 to 300 K; La/sub 3/Ga/sub 5/SiO/sub 14/; high-loss dielectric material; langasite; microwave frequencies; permittivity tensor; temperature coefficients; temperature compensated resonator; whispering-gallery mode; Buildings; Dielectric measurements; Frequency measurement; Lanthanum; Microwave frequencies; Microwave measurements; Permittivity measurement; Temperature; Tensile stress; Whispering gallery modes;

fLanguage

English

Journal_Title

Ultrasonics, Ferroelectrics, and Frequency Control, IEEE Transactions on

Publisher

ieee

ISSN

0885-3010

Type

jour

DOI

10.1109/TUFFC.2004.1320820

Filename

1320820