Séminaire du Laboratoire PhLAM par David CARPENTIER

Le séminaire sera animé par David CARPENTIER, Directeur de Recherche l'ENS Lyon, et aura pour thème "From topological materials to non-reciprocal optics ".

Résumé

Topology, a mathematical concept describing properties invariant under continuous deformations, has revolutionized condensed matter physics. Its first applications appeared in the 1970s with the classification of topological defects, while the 1980 discovery of the Quantum Hall Effect revealed that entire quantum phases could be topological.

In this seminar, I will introduce the concept of topological states of matter and then focus on Weyl semimetals—materials where electronic bands mimic topological defects in momentum space. Their unusual electrodynamics, governed by the chiral anomaly, leads to a Hall-like current under an electric field, without any magnetic field.

I will show that these materials exhibit intrinsic optical non-reciprocity: light propagation depends on its direction, even in magnetically neutral systems.  I will discuss its implications for both fundamental physics and technological applications.

Le résumé est à retrouver ici.