showing 7 related works from this author
Scanning optical microscopy modeling in nanoplasmonics
2012
International audience; One of the main purposes of nanoplasmonics is the miniaturization of optical and electro-optical components that could be integrable in coplanar geometry. In this context, we propose a numerical model of a polarized scanning optical microscope able to faithfully reproduce both photon luminescence and temperature distribution images associated with complex plasmonic structures. The images are computed, pixel by pixel, through a complete self-consistent scheme based on the Green dyadic functions (GDF) formalism. The basic principle consists in the numerical implementation of a realistic three-dimensional light beam acting as a virtual light tip able to probe the volume…
Photon antibunching in the optical near field
2010
International audience; We show that a combination of the field-susceptibility technique with the optical Bloch equations gives access to the temporal evolution of the populations and coherences of any quantum system placed in the optical near field of a nanostructure. In particular, we show that the near-field evanescent states, confined around dielectric or plasmonic particles, can be used to modify and control the photon statistics of the quantum system. This theoretical scheme leads to second-order autocorrelation functions in good agreement with recent experimental measurements performed with nitrogen-vacancy center in diamond nanocrystals placed in interaction with gold nanoparticles.
Acoustic vibrations of metal nanoparticles: high order radial mode detection
2004
The vibrational radial modes of silver nanospheres embedded in a glass matrix are investigated using a high sensitivity femtosecond pump-probe technique. The results yield evidence for coherent launching of the fundamental and higher order radial modes in agreement with a sphere dilation mediated excitation model. The results are consistent with low-frequency Raman scattering experiments.
Manipulating and squeezing the photon local density of states with plasmonic nanoparticle networks
2010
International audience; In this Brief Report, we show that when interconnected networks of gold particles are deposited onto a clean planar surface, they strongly modify the photonic local density of states LDOS in the immediate proximity of the self-assembled nanoparticles. They represent unique architectures for the subwavelength patterning of initially flat photonic LDOS. Moreover, we show that their local spectral signatures are well suited for the generation of sites able to enhance molecular fluorescence intensity.
Strongly directional scattering from dielectric nanowires
2017
It has been experimentally demonstrated only recently that a simultaneous excitation of interfering electric and magnetic resonances can lead to uni-directional scattering of visible light in zero-dimensional dielectric nanoparticles. We show both theoretically and experimentally, that strongly anisotropic scattering also occurs in individual dielectric nanowires. The effect occurs even under either pure transverse electric or pure transverse magnetic polarized normal illumination. This allows for instance to toggle the scattering direction by a simple rotation of the incident polarization. Finally, we demonstrate that directional scattering is not limited to cylindrical cross-sections, but…
Fano-resonances in High Index Dielectric Nanowires for Directional Scattering
2018
High refractive index dielectric nanostructures provide original optical properties thanks to the occurrence of size- and shape-dependent optical resonance modes. These modes commonly present a spectral overlap of broad, low-order modes (\textit{e.g}. dipolar modes) and much narrower, higher-order modes. The latter are usually characterized by a rapidly varying frequency-dependent phase, which - in superposition with the lower order mode of approximately constant phase - leads to typical spectral features known as Fano resonances. Interestingly, such Fano resonances occur in dielectric nanostructures of the simplest shapes. In spheroidal nanoparticles, interference between broad magnetic di…
Near-field coupling of a point-like dipolar source with a thin metallic film: Implication for STM plasmon excitations
2012
International audience; Recent experiments have shown that it is possible to excite surface plasmons on metallic films by injecting tunnel electrons from a sharp metal tip located in the immediate proximity of the sample. When working close to a bare metal film, the excitation of surface plasmons gives rise to typical circular patterns that can be recorded in both image and Fourier planes. Important physical parameters of surface plasmon propagation such as their propagation length can be extracted from these images. In this Letter, we discuss theoretically the physics of the plasmonic excitations induced by a STM tip.