The response of several ferroelectric systems to a THz electric pulse is investigated by atomistic schemes. Despite their dramatic differences in initial, intermediate, and final states, all these compounds exhibit a similar qualitative behavior when driven out of equilibrium by this pulse. Five different temporal regions occur in all of them: a first region for which these materials do not basically answer to the field; a second region where the electrical polarization quickly grows with the field; a third region during which the polarization continues to be enhanced while the field is now getting reduced, therefore resulting in a new form of negative capacitance; a fourth region where the polarization follows again the field, but by decreasing with time; and finally a region where the systems explore different hidden states under weak electric fields. The existence of these five regions results in a polarization-vs-electric field curve having a striking D-like shape in all of these ferroelectrics. The importance of ionic inertia into these effects is revealed.

Close

PrevNext

View figure in article

• Dielectric properties
• Ferroelectricity
• Permittivity
• Ferroelectrics
• Multiferroics
• Thin films
• Molecular dynamics
• Terahertz techniques