Publication

Structure and Energy of Charged Domain Walls in Ferroelectrics

Nava Setter, Alexander Tagantsev, Maxim Gureev
2009
Conference Papers

Abstract

The problem of the structure and energy of a charged 180-degree head-to-head domain wall is considered, using Landau theory. It was found that the scales controlling the wall structure can be very different from the Debye radius. Depending on the spontaneous polarization and the concentration of free carriers, these scales can be about the Thomas-Fermi screening length or about those typical for screening in nonlinear (Thomas-Fermi or Debye) regimes. In the typical case of perovskites, like BaTiO3, at room temperature, domain wall width is about the spatial scale of the nonlinear Thomas-Fermi screening.

Official source

https://infoscience.epfl.ch/entities/publication/ae843b97-4017-4158-b0be-235ec0711d39

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Nava Setter, Alexander Tagantsev, Maxim Gureev
2009
Conference Papers

Abstract

Official source

https://infoscience.epfl.ch/entities/publication/ae843b97-4017-4158-b0be-235ec0711d39

About this result

Related concepts (8)

Fermi gas

A Fermi gas is an idealized model, an ensemble of many non-interacting fermions. Fermions are particles that obey Fermi–Dirac statistics, like electrons, protons, and neutrons, and, in general, particles with half-integer spin. These statistics determine the energy distribution of fermions in a Fermi gas in thermal equilibrium, and is characterized by their number density, temperature, and the set of available energy states. The model is named after the Italian physicist Enrico Fermi.

Electric-field screening

In physics, screening is the damping of electric fields caused by the presence of mobile charge carriers. It is an important part of the behavior of charge-carrying fluids, such as ionized gases (classical plasmas), electrolytes, and charge carriers in electronic conductors (semiconductors, metals). In a fluid, with a given permittivity ε, composed of electrically charged constituent particles, each pair of particles (with charges q1 and q2) interact through the Coulomb force as where the vector r is the relative position between the charges.

Debye length

In plasmas and electrolytes, the Debye length (Debye radius or Debye–Hückel screening length), is a measure of a charge carrier's net electrostatic effect in a solution and how far its electrostatic effect persists. With each Debye length the charges are increasingly electrically screened and the electric potential decreases in magnitude by 1/e. A Debye sphere is a volume whose radius is the Debye length. Debye length is an important parameter in plasma physics, electrolytes, and colloids (DLVO theory).

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