Regensburg 2010 – scientific programme

Parts | Days | Selection | Search | Downloads | Help

DF: Fachverband Dielektrische Festkörper

DF 5: Multiferroics II (Joint Session of MA, DF, KR, DS)

DF 5.6: Talk

Monday, March 22, 2010, 15:15–15:30, H3

Ferroelectric properties of BiFeO₃ thin films under mechanical stress — •Martin Hoffmann, Oliver Mieth, and Lukas M. Eng — Institut für Angewandte Photophysik, Technische Universität Dresden, D-01062 Dresden

Since ferroelectric properties (polarization, coercive field, etc.) of thin films can differ dramatically from the corresponding bulk values due to lattice-mismatch-induced strain, the systematic investigation of the impact of mechanical stress on the nm-length-scale is an indispensable step towards the general understanding of ferroic thin film physics.

In the present study, 150-nm-thick multiferroic BiFeO₃ films grown on (001)-oriented SrTiO₃ substrates were inspected with piezoresponse force microscopy (PFM) towards their ferroelectric domain distribution and their local ferroelectric hysteresis behavior under both tensile and compressive stress.

The systematic variation of the externally applied mechanical stress by substrate bending allowed us to compensate or to enhance the strain effect, which can be quantified by monitoring the coercive field as a function of the bending angle.