Abstract
The dielectric constants and loss for pure single crystals of calcium tungstate and for neodymium- and gadolinium-doped crystals have been measured from 1 to 40 MHz. At 20‡ C the values for pure calcium tungstate areε a′ = 11.3±0.4,ε c′ = 9.1±0.4, at 1 MHz. These agree closely with Brower and Fang's data and increase very slightly with frequency. Doping at levels of less than 1.0 at.% produced no measurable change inε a′ orε c′. The dielectric loss, tanδ, which was isotropic, was about 5×10−3 for all specimens at 1 MHz; at higher frequencies, tan‡ increased and, in the neodymium-doped crystals, the high frequency loss was found to be concentration dependent.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
A. V. Komandin, R. D. Shapovalova andN. P. Mikhailova,Russian J. Phys. Chem. 34 (1960) 979.
W. S. Brower andP. H. Fang,J. Appl. Phys. 40 (1969) 4988;ibid 38 (1967) 2391.
A. Zalkin andD. H. Templeton,J. Chem. Phys. 40 (1964) 501.
G. Brown, C. J. Kirkby andJ. S. Thorp,J. Mater. Sci. 9 (1974) 65.
J. S. Thorp, H. P. Buckley andG. Brown,ibid 9 (1974) 864.
Marconi Instruments Ltd., Handbook No. OM 1245, (1960).
A. H. Scott andH. L. Curtis,J. Res. Nat. Bur. Stand. 22 (1939) 747.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Thorp, J.S., Ammar, E.A.E. The dielectric constants of CaWO4, Nd/CaWO4 and Gd/CaWO4 . J Mater Sci 10, 918–922 (1975). https://doi.org/10.1007/BF00823207
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00823207