2019/09/24 by Émilie Sakat, Emilie Sakat, Sakat, Emilie +10
Engineering · Materials Science · Physics and Astronomy · #FOS: Physical sciences #Gold and Silver Nanoparticles Synthesis and Applications #Optics (physics.optics) #Photonic Crystals and Applications #Plasmonic and Surface Plasmon Research #physics.optics
paper · pdf · doi:10.48550/arxiv.1909.10800
12 pages, 4 figures
openalex publication_date 2019/09/24 · arxiv created 2020/04/10 · arxiv updated 2020/04/13 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We study light absorption by a dipolar absorber in a given environment, which can be a nanoantenna or any complex inhomogeneous medium. From first-principle calculations, we derive an upper bound for the absorption, which decouples the impact of the environment from the one of the absorber. Since it is an intrinsic characteristic of the environment regardless of the absorber, it provides a good figure of merit to compare the ability of different systems to enhance absorption. We show that, in the scalar approximation, the relevant parameter is not the field enhancement but the ratio between the field enhancement and the local density of states. Consequently, a plasmonic structure supporting hot spots is not necessarily the best choice to enhance absorption. We also show that our theoretical results can be applied beyond the scalar approximation and the plane-wave illumination.