Webinar du 18/03/2025, donné par Joshua Davis (CRPP, Université de Bordeaux) pour le GDR Ondes et organisé par le groupement thématique :
GT2 : Physique et ingénierie des structures sub-longueur d'onde
Cette vidéo fait partie d'une série de trois:
1 - https://youtu.be/-r73F_Q0Z9E par Alexandre Baron
2 - https://youtu.be/YOYeqwUsQJc par Joshua Davis
3 - https://youtu.be/Kqi0lgGeOFw par Nigar Namazzade
Résumé:
We have optimized and analyzed the optical emission from a magnetic dipole (MD) transition in dielectric-core–metallic-satellite nanostructures (N-pods). Their geometries are formal solutions to the Thomson problem. Our analysis employs quasi-normal modes (QNMs), which offer a significant advantage over traditional real-frequency approaches, helping with the exploration and insight of the physical behaviour with respect to the parameter space. We demonstrate that highly symmetrical N-pods, which can currently be fabricated, are excellent candidates for achieving a large, orientation- and volume-independent magnetic Purcell factor with minimal loss. Additionally, we successfully suppress the electric dipole (ED) transition, obtaining a magnetic branching ratio exceeding 95% for nearly all N-pod particles. For particles exhibiting a high degree of symmetry, radiated magnetic Purcell factors as high as 180 are reached.