Ferroelectric Polarization Reversal vs Pump Spot Shape

TL;DR

This paper investigates how shaping the pump spot can facilitate ferroelectric polarization reversal by minimizing depolarizing fields, demonstrating the process through calculated polarization dynamics under mid-IR pumping.

Contribution

It introduces a method of using elongated pump spot shapes to enable polarization reversal in ferroelectrics, addressing the depolarizing field challenge.

Findings

Polarization reversal is achievable with optimized pump spot shape.

Elongated pump spots reduce depolarizing fields during reversal.

Calculated dynamics support experimental feasibility.

Abstract

It has recently been shown that the polarization of a ferroelectric can be strongly affected by light pumping or even transiently reversed by mid-IR pumping within a record short subpicosecond timescale. It was then suggested that the reversal of polarization is most likely prevented by the depolarizing field that appears during the process. To minimize the effect of the depolarizing field, I propose to create an elongated domain by choosing a corresponding pump spot shape. I calculate the polarization dynamics for a particular experimental setup with mid-IR pumping and show that the polarization reversal is possible in this case.