TY - JOUR
T1 - Thermal-pulse tomography of space-charge and polarization distributions in electret polymers
AU - Mellinger, Axel
AU - Flores-Suárez, Rosaura
AU - Singh, Rajeev
AU - Wegener, Michael
AU - Wirges, Werner
AU - Gerhard, Reimund
AU - Lang, Sidney B.
N1 - Funding Information:
Acknowledgments The authors would like to thank Lucas F. Santos (Instituto de Física de São Carlos, Brazil) for providing the electron-beam charged PTFE samples. The equipment was funded in part by the European Regional Development Fund. R.S. acknowledges financial support from the German Academic Exchange Service (DAAD).
PY - 2008/12
Y1 - 2008/12
N2 - A new, non-destructive technique for the analysis of electret materials is presented. Thermal-pulse tomography produces three-dimensional images of space-charge and polarization distributions with a lateral resolution of better than 50 μm and a depth resolution of less than 0.5 μm. A focused-pulsed laser heats a circular spot on the opaque upper electrode. While diffusing through the sample, the thermal pulse causes local changes in the sample geometry or dielectric properties, resulting in a short-circuit current in the presence of space charge or electric dipoles. From the transient current, the distribution of the internal electric field can be reconstructed by means of scale transformation or regularization methods.
AB - A new, non-destructive technique for the analysis of electret materials is presented. Thermal-pulse tomography produces three-dimensional images of space-charge and polarization distributions with a lateral resolution of better than 50 μm and a depth resolution of less than 0.5 μm. A focused-pulsed laser heats a circular spot on the opaque upper electrode. While diffusing through the sample, the thermal pulse causes local changes in the sample geometry or dielectric properties, resulting in a short-circuit current in the presence of space charge or electric dipoles. From the transient current, the distribution of the internal electric field can be reconstructed by means of scale transformation or regularization methods.
KW - Electret
KW - LIMM
KW - Polarization
KW - Polyvinylidene fluoride
KW - Space charge
KW - Thermal-pulse tomography
UR - http://www.scopus.com/inward/record.url?scp=57749180406&partnerID=8YFLogxK
U2 - 10.1007/s10765-008-0532-8
DO - 10.1007/s10765-008-0532-8
M3 - Article
AN - SCOPUS:57749180406
VL - 29
SP - 2046
EP - 2054
JO - International Journal of Thermophysics
JF - International Journal of Thermophysics
SN - 0195-928X
IS - 6
ER -