Ionic Gating Driven Polarization Control in Ultra-Thin and Leaky Ferroelectrics

Ionic liquid (IL) gating allows large electric fields to be achieved at the interface— providing an ability to control, manipulate, and elevate unique phenomena that can arise in the interfaced solid materials. Here, Ionic gating is used to induce reversible polarization switching in ultrathin and highly defective ferroelectric films. Long range electrostatic charge control is induced by modifying the electric double layer at an IL–PbZr_0.2Ti_0.8O₃ interface which drives electrostatic and electrochemical control of polarization orientation in the ferroelectric layer. The localized nature of the ionic gating mechanism forbids the leakage current which has historically limited the switching of ultra-thin and/or electrically leaky ferroelectric films in solid metal-gated capacitor devices. This is demonstrated on ultrathin films and in intentionally grown massively defective films with > 30% coverage of direct conducting channels running from surface to ground. We will close by discussing how the transient switching and the ability to manipulate static analog phase transitions might impact future technologies.