Accueil >
Production scientifique
(408) Production(s) de l'année 2015
|
|
Non-linear rheology and fracture in polymer-based viscoelastic fluids
Auteur(s): Ramos L.
Conférence invité: 23ème Congrès Général de la Société Française de Physique (strasbourg, FR, 2015-08-27)
|
|
|
Black Phosphorus Terahertz Photodetectors.
Auteur(s): Viti Leonardo, Hu Jin, Coquillat D., Knap W., Tredicucci Alessandro, Politano Antonio, Vitiello Miriam serena
(Article) Publié:
Advanced Materials, vol. p.201502052 (2015)
PMID 26270791
DOI: 10.1002/adma.201502052
WoS: 000362727900016
192 Citations
Résumé: The first room-temperature terahertz (THz)-frequency nanodetector exploiting a 10 nm thick flake of exfoliated crystalline black phosphorus as an active channel of a field-effect transistor, is devised. By engineering and embedding planar THz antennas for efficient light harvesting, the authors provide the first technological demonstration of a phosphorus-based active THz device.
|
|
|
AlGaN/GaN HEMT's photoresponse to high intensity THz radiation
Auteur(s): Diakonova N., But D., Coquillat D., Knap W., Drexler C., Olbrich P., Karch J., Schafberger M., Ganichev S. D., Ducournau Guillaume, Gaquière Christophe, Poisson M. -A., Delage S., Cywinski G., Skierbiszewski C.
(Article) Publié:
Opto-Electronics Review, vol. 23 p.195-199 (2015)
Texte intégral en Openaccess :
Ref HAL: hal-01190762_v1
DOI: 10.1515/oere-2015-0026
WoS: 000358354800002
Exporter : BibTex | endNote
7 Citations
Résumé: We report on the photoresponse dependence on the terahertz radiation intensity in ALGaN/GaN HEMTs. We show that the ALGaN/GaN HEMT can be used as a THz detector in CW and in pulsed regime up to radiation intensity of several kW/cm2. The dynamic range in the pulsed regime of detection can be more than 2 decades. We observed that the photoresponse of the HEMT could have a compound composition if two independent parts of the transistor are involved in the detection process; this result indicates that a more simple one channel device may be preferable on the detection purpose.
|
|
|
From elastic properties to macroscopic physical properties of silicate glasses melts
Auteur(s): Ruffle B.
Conférence invité: 14th International Conference on The Physics of Non-Crystalline Solids (Niagara Falls, NY, US, 2015-09-21)
|
|
|
Structural relaxation dynamics at the atomic scale in a sodium silicate glass
Auteur(s): Ruffle B.
Conférence invité: XXIV International Materials Research Congres (Cancun, MX, 2015-08-17)
|
|
|
Perforation of a radially expanding sheet of a dilute emulsion
Auteur(s): Ligoure C.
Conférence invité: Lorentz center workshop "Liquid fragmentation in Nature and Industry" (Leiden, NL, 2015-06-29)
Ref HAL: hal-01187419_v1
Exporter : BibTex | endNote
Résumé: We study the destabilization mechanism of thin liquid sheets expanding in air and show that dilute oil-in-water emulsion-based sheets disintegrate through the nucleation and growth of holes that perforate the sheet. The velocity and thickness fields of the sheet are not perturbed by holes and hole opening follows a Taylor-Culick law. We find that a pre-hole, which widens and thins out the sheet with time, systematically precedes the hole nucleation. The growth dynamics of the pre-hole follows the law theoretically predicted for a liquid spreading on another liquid of higher surface tension due to Marangoni stresses. Classical Marangoni spreading experiments quantitatively corroborate those findings.
|
|
|
The Role of Oil-in-water Emulsions in Controlling the Drop size Distribution of an Agricultural Spray
Auteur(s): Ligoure C.
Conférence invité: EMN Meeting on Droplets (PHUKET, Patong beach, TH, 2015-05-08)
Ref HAL: hal-01187396_v1
Exporter : BibTex | endNote
Résumé: Agricultural spraying involves atomizing a liquid stream through a hydraulic nozzle, thus forming a liquid sheet that is subsequently destabilized into drops. Standard adjuvants as dilute oil-in-water emulsions are known to influence the spray drop size distribution: the fraction of small drops responsible of spray drift is reduced. Although being documented, the physical mechanisms at the origin of the size increase of the drops remain unclear. To elucidate the mechanisms causing the changes on the drop size distribution, we investigate the influence of dilute emulsions on the destabilization mechanisms of liquid sheets. Model laboratory experiments based on the collision of a liquid tear on a small solid target are used to produce and visualize liquid sheets. With dilute oil-in-water emulsions, the liquid sheet is destabilized by the nucleation of holes in the sheet that perforate it during its expansion. The emulsion concentration and the size of the oil droplet of the emulsion are varied to rationalize their influence on the sheet destabilization mechanisms. The results obtained with the model laboratory experiments are compared to the measurement of the drop size distribution resulting from the destabilization of a conventional agricultural spray. The very good correlation between the number of perforation events and the volume fraction of small drops in the spray suggests (i) that the model experiment on liquid sheet is appropriate to investigate and gain an understanding of the physical mechanisms governing the spray drop size distribution and (ii) that the perforation destabilization mechanism of liquid sheets, which dominate for dilute emulsions, is at the origin of the increase of size of the spray. Finally the analysis of the of the kinetics of formation and growth of the holes allows to identify the physical origin of the perforation.
|