Universitiy of Potsdam

Applied Condensed Matter Physics

Prof. Dr. Reimund Gerhard
2016-11-04 16:30 by Manuel Schulze

The Piezoelectrically-generated pressure-step method (PPS)

The knowledge about polarization or space-charge distribution in charged polar polymers (polyvinylidene fluoride PVDF, piezo- and pyroelectric material) or in non-polar polymers (polytetrafluoroethylene PTFE, TeflonTM, electret material) is of general interest, both for fundamental research and for applications.

b-PVDF Teflon™
PVDF Teflon
Certain molecular groups act as dipoles and can be oriented in an electric field (permanent polarization). Certain non-polar polymer materials exhibit excellent charge-storage properties (electret materials).

Depending on the material and the poling or charging conditions we get different polarization or charge profiles:

electrode poling corona charging
unpoled room temperature
room temperature
poled 200°C
200

The PPS method allows for direct determination of polarization or charge profiles in the thickness direction of thin (10-100 ┬Ám) dielectrics.

How does the PPS method work? Continue on the next page...