arXiv subjects

Anaïs Sené

Publications and source records attributed to Anaïs Sené.

3 recordsLinked to original sources

arXiv2025

Morphology of Polarization States in Strained Ferroelectric Films

Ferroelectric thin films under epitaxial strain exhibit a variety of vortex-like topological polarization textures. To analyze them, we build on the Ginzburg-Landau-Devonshire framework and extend the previously introduced soft-domain approach. This formulation provides a compact variational theoretical description of polarization morphologies in strained PbTiO$_3$ films. It yields phase diagrams as a function of temperature, strain, and thickness, and clarifies the morphological structure of emergent topological states. The method is computationally efficient and offers practical guidance for experimental studies of ferroelectric nanostructures.

cond-mat.mtrl-sci↗

arXiv2015

Terahertz Electrodynamics of $180^\circ$ Domain Walls in Thin Ferroelectric Films

We investigate oscillation dynamics of a periodic structure of the $180^\circ$ domain walls in nanometricaly thin substrate-deposited ferroelectric films and superlattices. We calculate dynamic permittivity of such structures and reveal a collective resonance mode, which in the typical ferroelectric compounds, PbTiO3/SrTiO3, lies in the sub- and low THz frequency range of 0.3-3THz. We propose the reflection-absorbtion spectroscopy experiments to observe this mode.

cond-mat.mtrl-sci↗

arXiv2014

Polarization vortex domains induced by switching electric field in ferroelectric films with circular electrodes

We describe ferroelectric thin films with circular electrodes and develop a thermodynamic theory that explains previously mysterious experiments. It is found to be especially useful for restricted geometries such as microstructures for which boundary conditions are well known to play an important role in ferroelectric properties. We have explored a new switching mechanism, which consists of an inhomogeneous rotational motion of the polarization and leads to an extended vortex state. The vortex appearance exhibits characteristic properties of a first-order field-induced phase transition: three critical electric fields and the possibility of hysteresis behavior.

cond-mat.mtrl-sci↗