Coupled magnetic and electric phenomena open new avenues in ferroelectric memory devices and sensor technologies. The advanced study of these requires different techniques that are mainly based on capacitor-like geometries.
Our custom-made Magneto-electric workstation consists of a superconducting 7 Tesla magnet, a continuous flow cryostat (liquid-N2 or He operation) and custom-designed probes for use with samples in various forms (polycrystalline pellet, single crystal, film and capacitor topology composites) that altogether provide fully computer-controlled programmable measurements.
Advanced sample environments, with temperature and external stimuli sweeping capabilities, explore the induction of electric polarization (magnetization) by an external magnetic (electric) field.
The infrastructure utilizes a user-friendly LabView programmed interface that fulfills the requirements for characterization of the nanomaterials’ in terms of their dielectric permittivity, in an extended frequency range (50 Hz ≤ f ≤ 2 MHz; option with DC-bias ±40 V) and a broad temperature window (2 ≤ T ≤ 320 K). In addition to recording standard isothermal I-V characteristics, more demanding DC electric polarization as well as pyro-electric current experiments can be performed upon temperature sweeps, with the magnetic field (-7≤ H≤ +7 T) as an external stimulus.
A probe station with micromanipulated micrometric tips allow electrical testing (conductivity, frequency-dependent permittivity, ferroelectric polarization loops, etc) of devices in the 70-600 K temperature range under magnetic fields up to 10 kOe. The facility permits testing photoresponse under variable wavelengths in the visible optical range.
Magnetic/ferroelectric/dielectric characterization @ Laboratory for Multiscale Materials Experiments
4-point and 2-point probe resistivity measurements, AC resistivity, Hall effect, I-V curve, critical current