Seminars

PMMH’s weekly seminar is held every Friday at 11 am (map)

Contact :
Stéphane Perrard
Etienne Reyssat
Virgile Thiévenaz
responsables-seminaires (arobase) pmmh.espci.fr

PMMH
BARRE CASSAN
BAT A 1ER ETAGE CASE 18
7 QUAI SAINT BERNARD
75005 PARIS
France

Tel : (33) 1 40 79 45 22


Séminaire PMMH - Serge Berthier (INSP)

Vendredi 6 janvier 2023 de 11h00 à 12h00 - Salle réunion PMMH 1

Natural Photonics

Photonics, the art of manipulating light, is a relatively recent science. To manage light, to confine it, to slow it down, to orient it... you have to put yourself on its scale, that of the wavelength, that is to say, to create periodic structures (like an electromagnetic wave) who's the period is of the order of a few tenths of the wavelength. Typically for the visible : 50 to 100 nm. We are stammering in this area, but many living organisms, mainly arthropods, because of their large number, but also birds, reptiles, fish, etc. have developed such structures, called "photonic crystals", to manage their interactions with the various sources of electromagnetic radiation to which they are subjected. From ultraviolet to thermal infrared, we will show various examples of light-insect interactions in each of these areas : Fluorescence and UV protection ; physical colours, colour change in the visible, perception and production of polarization light ; thermal management and detection in infrared range.
What does this research tell us :
That a “good” structure is always multifunctional (a butterfly wing is only used incidentally to fly !).
That this structure is optimized on average (No function is privileged over the others)
That it is extremely economical in terms of chemical elements (Most structures only use 4 to 5 elements of the periodic table).

Such achievements can only be obtained thanks to the structural complexity (which overcomes the economy of elements) and a controlled degree of disorder which ensures the average optimization of the structure and its multifunctionality. If we do not know how to control disorder, we can measure it. We'll see how.

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Seminars  (4)

  • Séminaire PMMH - Francesca Borghi Università degli Studi di Milano
    Vendredi 20 juin de 11h00 à 12h00 - Salle réunion PMMH 1
    REPROGRAMMABLE HARDWARE FOR DATA PROCESSING AT THE EDGE : A NEW COMPUTING PARADIGM BASED ON NEUROMORPHIC SYSTEMS
    The brain's ability to perform efficient and fault-tolerant data processing is strongly related with its peculiar interconnected adaptive architecture, based on redundant neural circuits interacting at different scales. By emulating the brain's processing and learning mechanisms, computing technologies strive to (…)
  • Séminaire PMMH - Francesca Borghi Università degli Studi di Milano
    Vendredi 20 juin de 11h00 à 12h00 - Salle réunion PMMH 1
    REPROGRAMMABLE HARDWARE FOR DATA PROCESSING AT THE EDGE : A NEW COMPUTING PARADIGM BASED ON NEUROMORPHIC SYSTEMS
    The brain's ability to perform efficient and fault-tolerant data processing is strongly related with its peculiar interconnected adaptive architecture, based on redundant neural circuits interacting at different scales. By emulating the brain's processing and learning mechanisms, computing technologies strive to (…)
  • Séminaire PMMH - Salvatore Federico (University of Calgary, Canada)
    Vendredi 4 juillet de 11h00 à 12h00 - Salle réunion PMMH 1
    Continuum Mechanics of Hydrated Fibre-Reinforced Soft Tissues
    Biological tissues can be represented as bi-phasic continua, with a porous solid phase saturated by an interstitial fluid and reinforced by collagen fibers. This lecture will give an overview of the modelling techniques for fibre-reinforced porous composite materials with statistical orientation of the fibers. Both (…)
  • Séminaire PMMH - Salvatore Federico (University of Calgary, Canada)
    Vendredi 4 juillet de 11h00 à 12h00 - Salle réunion PMMH 1
    Continuum Mechanics of Hydrated Fibre-Reinforced Soft Tissues
    Biological tissues can be represented as bi-phasic continua, with a porous solid phase saturated by an interstitial fluid and reinforced by collagen fibers. This lecture will give an overview of the modelling techniques for fibre-reinforced porous composite materials with statistical orientation of the fibers. Both (…)

Information for the speakers

The audience is composed of people with rather heterogeneous backgrounds including specialists in solids, fluids, granular flows, statistical physics... so the idea is to keep your talk understandable by people not necessarily working in your field... The seminar time slot runs from 11am to noon so the best is to make the talk last around 45 minutes to leave some time for discussion.

Link to cofee seminar (internal, every Thursday)


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Practical information

Laboratoire : 01 40 79 45 22
Directeur : Ramiro GODOY DIANA
Codirecteur : Laurent DUCHEMIN
Administratrice : Frédérique AUGER (01 40 79 45 22)
Gestionnaire : Claudette BAREZ (01 40 79 58 53)
Courriel : dir (arobase) pmmh.espci.fr