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The vacuum polarization energy is the leading quantum correction to the classical energy of a soliton. We study this energy for two-component solitons in one space dimension as a function of the soliton’s topological charge. We find that both the classical and the vacuum polarization energies are linear functions of the topological charge with a small offset. Because the combination of the classical and quantum offsets determines the binding energies, either all higher charge solitons are energetically bound or they are all unbound, depending on model parameters. This linearity persists even when the field configurations are very different from those of isolated solitons and would not be apparent from an analysis of their bound state spectra alone. Published by the American Physical Society2025
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This content will become publicly available on November 1, 2025
Conic sections in ferroelectric nematics: Experiments and mathematical modeling
The domain structure of a fluid ferroelectric nematic is dramatically different from the domain structure of solid ferroelectrics since it is not restricted by rectilinear crystallographic axes and planar surface facets. We demonstrate that thin films of a ferroelectric nematic seeded by colloidal inclusions produce domain walls (DWs) in the shape of conics such as a parabola. These conics reduce the bound charge within the domains and at the DWs. An adequate description of the domain structures requires one to analyze the electrostatic energy, which is a challenging task. Instead, we demonstrate that a good approximation to the experimentally observed polydomain textures is obtained when the divergence of spontaneous polarization—which causes the bound charge—is heavily penalized by assuming that the elastic constant of splay in the Oseen-Frank energy is much larger than those for twist and bend. The model takes advantage of the fact that the polarization vector is essentially parallel to the nematic director throughout the sample. Published by the American Physical Society2024
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- PAR ID:
- 10598588
- Publisher / Repository:
- Physical Review Research
- Date Published:
- Journal Name:
- Physical Review Research
- Volume:
- 6
- Issue:
- 4
- ISSN:
- 2643-1564
- Subject(s) / Keyword(s):
- Ferroelectric nematic space charge domain walls
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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