Broadband Characterization of Multiferroic Thin-Films

The electromagnetic response of ferroelectric and multiferroic thin films at microwave frequencies is important for a fundamental understanding of these materials, as well for potential applications in electronics and communications systems. We explore the high-frequency response (to 40 GHz) of dielectric thin-film samples using a distributed measurement technique that utilizes patterned transmission line devices. We combine these measurements with measurements of lumped-element capacitors at lower frequencies (100 Hz - 100 MHz) to obtain true broadband measurements (100 Hz - 40 GHz) of the complex permittivity of thin film samples as a function of temperature, and electric- or magnetic-field bias.