Temperature dependence of the permittivity and loss tangent of high-permittivity materials at terahertz frequencies

An analysis including the temperature dependence of the permittivity and loss tangent of three low-cost and high-permittivity materials (zirconium-tin-titanate, alumina, and titanium-dioxide) in the terahertz frequency range is presented. Such dielectric materials find varied applications in microwave and terahertz systems and components. Their effective use under varying environmental conditions or in space applications requires a detailed knowledge about temperature dependencies. Here, measurements using broad-band terahertz time-domain spectroscopy are presented in the temperature range from 10 to 323 K. It is shown that zirconium-tin-titanate and alumina provide a good thermal stability of the permittivity, whereas the permittivity of titanium-dioxide exhibits a strong dependence on the temperature.