Nanoscale Ferroelectric Domains
Functionalization of ferroelectric materials emerged the growing interest in exploration of such nano-scale self-organized structures as polarization domains. For a long time it was believed that the regular domain patterns can appear only in ferromagnetic systems.
However, it was convincingly demonstrated over the last decade that the steady Landau-Kittel polarization domains do arise in the nano-scale strained films, superlattices nanoroads and nanodots.
Several recent results concerning their dynamic and static properties will be reviewed.
First, we consider the formation of domains in ultrathin films and superlattices of ferroelectric oxides and report a comprehensive description of their electrodynamic response. In particular we demonstrate that the field-induced domain wall motion can be in the origin of the recently observed fascinating “negative capacitance effect” effect.
Then, we show that the frequency-dependent permittivity of such system reveals the collective resonance mode in the near-terahertz frequency range that can be excited and detected by the methods of reflection absorption spectrometry. This finding can provide an important impact for the development of the ferroelectric-based terahertz optics and plasmonics.
Finally we consider the unconventional multibit polarization switching in ferroelectric nanodots, with formation of the intermediate domain states or/and chiral polarization skyrmions that can be useful for design of the memory-storage devices.