A feedback model for relaxors

Abstract

The transition from a ferroelectric to a relaxor is described. Asymmetric double-well potentials for fluctuating charges, dipoles or polar nanoregions and a feedback between these double wells are employed. Tuning the intrinsic asymmetry it is possible to describe either a ferroelectric state or a relaxor behavior. While in ferroelectrics with an ordered crystal lattice the intrinsic asymmetry is small, disorder in the amorphous state can result in double wells with higher asymmetry causing a relaxor response.

Keywords:

• Relaxor
• Weiss field
• Feedback model
• Asymmetric double well potential

Additional information

Funding

This work was supported by the Deutsche Forschungsgemeinschaft, project KL 654/41-1.