Electrical transport measurements are typically limited to samples that are less than 10 mm x 10 mm in lateral extent and several millimetres in thickness. Powders are typically pressed into geometries (sometimes with the aid of binders) that satisfy these dimensional requirements. The currently available measurement options are:
- DC resistivity: This can be done in either 2- or 4-wire mode. 4-wire mode is preferred, as it greatly reduces the contributions from lead and contact resistances.
- ACtransport: This can be used to measure a variety of electrical properties, such as conductivity, resistivity, and Hall coefficient.
- Multi-function probe: This can be used to measure a variety of properties, including electrical transport and magnetic properties.
Within the approximately 10 mm x 10 mm mounting area within the instrument, there is typically room for up to 3 samples, provided they are sized appropriately.
The Electrical Transport Option (ETO) enables AC electrical transport measurements of samples using a 2- or 4-probe lead configuration. The 2-probe configuration is suitable for all ranges of samples, while the 4-probe configuration is especially useful for looking at resistive samples, or those where pulsed current measurements could be utilized such as when studying memristors.
The 4-probe configuration is advantageous in terms of reducing the contribution of lead and contact resistances. With proper lead placement, the Hall coefficient can also be measured in 4-wire mode.