Coercive Field Values and Shape Features of FE Loops in PMN-20PT at Low Temperatures

The classic way to describe ferroelectric (FE) loops comes down to specifying only basic parameters. Usually, it is not enough to fully describe the loop shape. In our study we proposed a simple method which provides information about asymmetry in measured FE loops or switching rate. A three-percentile method was proposed for a more detailed description of FE loops. Coercive field values and FE loop shape properties of PMN-20PT single crystal at low temperatures were determined. Analysis of FE loops shape measured at different frequencies led us to assumption of existence of several polarization switching mechanisms with different characteristic times. The model function for temperature dependence of corrective field was refined.