Growth and dielectric properties of Ta2O5 single crystal fibers

Abstract

Single crystal fibers of Ta2O5 have been grown by the Laser Heated Pedestal Growth (LHPG) technique up to several cm in length with diameters of 1.1 mm. The as grown crystal, characterized by X-ray diffraction, dielectric measurement and thermal expansion analysis, has Htri-Ta2O5 symmetry. Dielectric permittivity, loss tangent along [001] and [110] direction were investigated over the temperature range from -180°C to 100°C. Large dielectric anisotropy in Ta2O5 single crystal was observed. At room temperature, the dielectric permittivity (1 MHz) along the [001] is 33.2, while that along the [110] is 231.9. The reason of dielectric enhancement in Ta2O5 crystal grown by LHPG was also discussed.Single crystal fibers of Ta2O5 have been grown by the Laser Heated Pedestal Growth (LHPG) technique up to several cm in length with diameters of 1.1 mm. The as grown crystal, characterized by X-ray diffraction, dielectric measurement and thermal expansion analysis, has Htri-Ta2O5 symmetry. Dielectric permittivity, loss tangent along [001] and [110] direction were investigated over the temperature range from -180°C to 100°C. Large dielectric anisotropy in Ta2O5 single crystal was observed. At room temperature, the dielectric permittivity (1 MHz) along the [001] is 33.2, while that along the [110] is 231.9. The reason of dielectric enhancement in Ta2O5 crystal grown by LHPG was also discussed.