Slow relaxation of the polarization in pulsed laser ablated highly oriented ferroelectric thin films

C. Björmander; J. Wittborn; K.V. Rao; E. Dan Dahlberg

doi:doi:10.1051/jp4:1998915

Issue		J. Phys. IV France Volume 08, Number PR9, December 1998 2^nd European Meeting on Integrated Ferroelectrics EMIF 2


Page(s)		Pr9-89 - Pr9-99
DOI		https://doi.org/10.1051/jp4:1998915

2^nd European Meeting on Integrated Ferroelectrics
EMIF 2

J. Phys. IV France 08 (1998) Pr9-89-Pr9-99
DOI: 10.1051/jp4:1998915

Slow relaxation of the polarization in pulsed laser ablated highly oriented ferroelectric thin films

C. Björmander¹, J. Wittborn², K.V. Rao² and E. Dan Dahlberg³

¹ Materials Science Division, Argonne National Laboratory.
² Department of Condensed Matter Physics, Royal Institute of Technology, 100 44 Stockholm, Sweden
³ Tate Laboratory of Physics, University of Minnesota.

Abstract
The relaxation of the polarization (as determined by the pyroelectric effect) of high quality laser ablated films of PbZr_0.52Ti_0.48O₃ has been measured after saturation with an applied electric field. The decay is observed to be quasilogrithmic over four decades in time. Analysis of measurements of the remanent polarization and the depolarization remanence are consistent with the depolarization field providing a polarization-state-dependent field of the correct direction to drive the decay. Also, the quasilogrithmic time dependence is consistent with a model for slow relaxation or creep with the depolarization field the driving field for the decay.These observations along with our AFM measurements imply that for maximum polarization stability a ferroelectric film should consist of decoupled grains. The optimum grain size should be the maximum grain size which does not support domain walls.