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This work lays out the two-potential framework for the constitutive modeling of dielectric elastomers. After its general presentation, where the constraints imposed by even electromechanical coupling, material frame indifference, material symmetry, and entropy imbalance are all spelled out, the framework is utilized to put forth a specific constitutive model for the prominent class of isotropic incompressible dielectric elastomers. The model accounts for the non-Gaussian elasticity and electrostriction typical of such materials, as well as for their deformation-enhanced shear thinning due to viscous dissipation and their time-dependent polarization due to electric dissipation. The key theoretical and practical features of the model are discussed, with special emphasis on its specialization in the limit of small deformations and moderate electric fields. The last part of this paper is devoted to the deployment of the model to fully describe the electromechanical behavior of a commercially significant dielectric elastomer, namely, the acrylate elastomer VHB 4910 from 3M.
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Tailored Nonlinear Anisotropy in Mie‐Resonant Dielectric Oligomers
Abstract The field of Mie‐resonant nanophotonics has attracted a lot of attention recently due to many promising applications in linear and nonlinear metaoptics. Optically induced magnetic resonances define novel characteristics of isolated high‐index dielectric nanoparticles and their oligomers. Here, the orientation‐dependent nonlinear frequency generation from dielectric oligomers with different symmetries, being all characterized by isotropic linear response, is demonstrated. The rotational dependence of the third‐harmonic signal emitted by the nanoparticle oligomers in accord with their point‐group symmetry (e.g., C3 or C4) is observed experimentally, while their linear scattering remains isotropic. The experimental data are in a good agreement with numerical simulations and the symmetry analysis of the nonlinear susceptibility tensor. The results open a new avenue for tailoring nonlinear properties of nanoscale structures.
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- Award ID(s):
- 1719875
- PAR ID:
- 10445747
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Optical Materials
- Volume:
- 7
- Issue:
- 20
- ISSN:
- 2195-1071
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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