Pantheon SEMPARIS Le serveur des séminaires parisiens Paris

Statut Confirmé
Domaines cond-mat
Date Lundi 15 Octobre 2018
Heure 14:00
Institut LPTM
Salle 4.13 St Martin II
Nom de l'orateur Bailly Reyre
Prenom de l'orateur Aurélien
Addresse email de l'orateur
Institution de l'orateur LPTM UCP Cergy Pontoise
Titre Mobile spins on lattice as model for liquid crystals and topological excitations and skyrmions
Résumé We are initially interested in the phase transitions that take place in liquid crystals (LC), from a theoretical and numerical point of view. Indeed, the results presented here are derived from Monte Carlo (MC) simulations and analytical developments based on statistical physics and condensed matter models. A strong analogy exists between spin systems and LC. For example, the latter have phases where the molecules are all aligned in the same direction (orientational order) comparable to spins in ferromagnetic materials. Other phases, called cholesteric, are characterized by a molecular arrangement similar to the helimagnetic structures. But liquid crystals being an intermediate state of matter, between the solid and the liquid phase, it is necessary to take into account the motions of the molecules in the models and to adapt accordingly the MC algorithm. It led us to study the dynamics leading to the formation of the nematic and smectic phases using a mobile Potts model. We have also studied the formation of specific topological structure like skyrmions that are structures observed (theorically) in LC. We use a Dzyaloshinski-Moria (DM) interaction of strength D in addition to an exchange interaction J to study properties of thin films.
Numéro de preprint arXiv
Fichiers attachés

Pour obtenir l' affiche de ce séminaire : [ Postscript | PDF ]

[ Annonces ]    [ Abonnements ]    [ Archive ]    [ Aide ]    [ ]
[ English version ]