Reversible optical control of macroscopic polarization in ferroelectrics

The optical control of ferroic properties is a subject of fascination for the scientific community, because it involves the establishment of new paradigms for technology(1-9). Domains and domain walls are known to have a great impact on the properties of ferroic materials(1-24). Progress is currently being made in understanding the behaviour of the ferroelectric domain wall, especially regarding its dynamic control(10-12,17,19). New research is being conducted to find effective methodologies capable of modulating ferroelectric domain motion for future electronics. However, the practical use of ferroelectric domain wall motion should be both stable and reversible (rewritable) and, in particular, be able to produce a macroscopic response that can be monitored easily(12,17). Here, we show that it is possible to achieve a reversible optical change of ferroelectric domains configuration. This effect leads to the tuning of macroscopic polarization and its related properties by means of polarized light, a non-contact external control. Although this is only the first step, it nevertheless constitutes the most crucial one in the long and complex process of developing the next generation of photo-stimulated ferroelectric devices.