Accueil >
Production scientifique
(153) Production(s) de l'année 2019
|
|
Metasurface-mediated anisotropic radiative heat transfer between nanoparticles 
Auteur(s): Zhang Yong, Antezza M., Yi Hing-liang, Tan He-ping
(Article) Publié:
Physical Review B, vol. 100 p.085426 (2019)
Ref HAL: hal-02267129_v1
DOI: 10.1103/PhysRevB.100.085426
Exporter : BibTex | endNote
Résumé: Metasurfaces, the two-dimensional (2D) counterpart of metamaterials, have recently attracted a great deal of
attention due to their amazing properties, including negative refraction, hyperbolic dispersion, and manipulation
of the evanescent spectrum. In this work, a theory model is proposed for the near field radiative heat transfer
(NFRHT) between two nanoparticles in the presence of an anisotropic metasurface. Specifically, the metasurface
is modeled as an array of graphene strips (GS), which is an ideal platform to implement any metasurface
topology, ranging from isotropic to hyperbolic propagation. The NFRHT between two nanoparticles are
significantly amplified when they are placed in the proximity of the GS, and regulated over several orders
of magnitude. In this configuration, the anisotropic surface plasmon polaritons (SPPs) supported by the GS
are excited and provide a new channel for the near-field energy transport. The dependence of conductance
between two nanoparticles on the orientation, the structure parameters, the chemical potential of the GS, and
the interparticle or the particle-surface distances are analyzed by clearly identifying the characteristics of the
anisotropic SPPs such as dispersion relations, propagation length, and decay length. These results demonstrate a
powerful method to regulate the energy transport in particle systems, and create a way to explore the anisotropic
optical properties of the metasurface based on the measured heat transfer properties.
|
|
|
|
Drop Impact experiments: a tool to investigate fast biextensional flow of polymeric liquids
Auteur(s): Ligoure C.
Conférence invité: Workshop : Polymers in fast flows (Anacapri, IT, 2019-07-29)
Résumé: The collision of a liquid drop against a small target results in the formation of a thin liquid sheet that extends radially until it reaches a maximum diameter and subsequently recedes. We investigate the corresponding fast bi-extensional flows of high molecular weight homopolymers, and supramolecular living polymer solutions. Both systems exhibit shear thinning behavior. Experiments indicate the presence of two expansion regimes: the capillary regime, where the maximum expansion does not depend on the fluid’s zero-shear viscosity, and the viscous regime, where the expansion is reduced with increasing polymer concentration (hence, zero-shear viscosity) due to viscous dissipation. The expansion process is expected to be controlled by a combination of shear (on the target) and biaxial (in air) deformations. We propose an approach toward a rational description of the phenomenon for Newtonian and non-Newtonian fluids by evaluating the viscous dissipation due to shear and extensional deformations, yielding a quantitative prediction of the maximum spreading factor of the sheet as a function of the relevant viscosity. We find that the biaxial viscosity is the appropriate quantity to describe the maximum expansion of both viscoelastic and viscous sheets. For solutions of polymeric thinning fluids, shear dissipation is negligible compared to extensional dissipation.
|
|
|
|
The multiple symmetry sustaining phase transitions of spin ice
Auteur(s): Raban V., Suen C. t., Berthier L., Holdsworth P. C. W.
(Article) Publié:
Physical Review B, vol. 99 p.224425 (2019)
Texte intégral en Openaccess : 
|
|
|
|
High-Pressure Softening of the Out-of-Plane A2u(Transverse-Optic) Mode of Hexagonal Boron Nitride Induced by Dynamical Buckling
Auteur(s): Segura A, Cusco R., Taniguchi T., Watanabe Kanji, Cassabois G., Gil B. , Artus L.
(Article) Publié:
The Journal Of Physical Chemistry C, vol. 123 p.17491 (2019)
|
