A testbed for high voltage, high bandwidth characterization of nonlinear dielectrics

The dielectric response of many high permittivity materials is nonlinear with both field and frequency. For example, ferroelectric materials exhibit a hysteretic polarization - electric field (P-E) response similar to the B-H curve of ferromagnetic materials. These P-E hysteresis loops are typically measured at low frequencies; the material behavior at high frequencies is less understood. To address this information gap, a test bed has been created to characterize non-linear material behavior at high frequencies and high voltages. This paper will report testbed goals in addition to design, assembly, analysis, and issues. Preliminary results will also be presented from commercially available nonlinear capacitors and in-house fabricated ferroelectric materials, including 10 nF non-linear BaTiO₃-based capacitors and 3 mm thick lead zirconate titanate (PZT)-based materials.