Contact-free reversible switching of improper ferroelectric domains by electron and ion irradiation

Focused ion beam (FIB) and scanning electron microscopy (SEM) are used to reversibly switch improper ferroelectric domains in the hexagonal manganite ErMnO3. Surface charging is achieved by local (positive charging) negative irradiation, which allows controlled polarization switching without need for electrical contacts. Polarization cycling reveals that domain walls tend return equilibrium configuration obtained as-grown state. The response of sub-surface studied FIB cross-sectioning, enabling imaging direction perpendicular applied electric field. results clarify how reversal manganites progresses at level domains, resolving both wall movements nucleation growth new domains. Our FIB-SEM based approach applicable all ferroelectrics where a sufficiently large field can be built up via surface charging, facilitating contact-free high-resolution studies fields 3D.