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arXiv · 1207.5906

Precise microwave characterization of MgO substrates for HTS circuits with superconducting post dielectric resonator

Janina E. Mazierska·Dimitri O. Ledenyov·Mohan V. Jacob·Jerzy Krupka
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Abstract

Accurate data of complex permittivity of dielectric substrates are needed for efficient design of HTS microwave planar circuits. We have tested MgO substrates from three different manufacturing batches using a dielectric resonator with superconducting parts recently developed for precise microwave characterization of laminar dielectrics at cryogenic temperatures. The measurement fixture has been fabricated using a SrLaAlO3 post dielectric resonator with DyBa2Cu3O7 end plates and silver-plated copper sidewalls to achieve the resolution of loss tangent measurements of 2 {\times} 10-6. The tested MgO substrates exhibited the average relative permittivity of 9.63 and tan δ from 3.7 {\times} 10-7 to 2 {\times} 10-5 at frequency of 10.5 GHz in the temperature range from 14 to 80 K.

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Janina E. Mazierska, Dimitri O. Ledenyov, Mohan V. Jacob, Jerzy Krupka. 2012-07-25. Precise microwave characterization of MgO substrates for HTS circuits with superconducting post dielectric resonator. https://doi.org/10.1088/0953-2048%2F18%2F1%2F004

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