Frederique de Fornel - Profile on Academia.edu (original) (raw)
Papers by Frederique de Fornel
Physical review, Mar 12, 2002
Nonresonant excitation of surface plasmon polaritons at discontinuities of a gold film is numeric... more Nonresonant excitation of surface plasmon polaritons at discontinuities of a gold film is numerically studied and experimentally observed with scanning near-field optical microscopy. It is shown that surface polaritons can be effectively launched at the edges of a metal film illuminated at an angle of incidence greater than the resonant angle of surface polariton excitation. The electromagnetic near-field distribution over a thin metal film exhibits significantly different features under resonant and nonresonant excitations due to different surface polariton excitation mechanisms. In the latter case the field distribution is determined by the interference of the excitation light and surface polaritons launched on air-metal and glass-metal interfaces. In the former case the interference of surface polariton modes excited on different interfaces of a metal film is dominating. The modulation depths of the respective interference patterns correspond to the efficiency of the intensity conversion of the excitation light at the metal discontinuities into surface polaritons of the order of 0.1-0.01 depending on an angle of incidence.
Bloch mode coupling investigation in silicon-on-insulator W1 photonic crystal waveguide
Proceedings of SPIE, Sep 15, 2004
ABSTRACT
Near-field modal microscopy of subwavelength light confinement in multimode silicon slot waveguides
Applied Physics Letters, Dec 22, 2008
Silicon-on-insulator slot waveguides are studied by scanning near-field optical microscopy. Image... more Silicon-on-insulator slot waveguides are studied by scanning near-field optical microscopy. Images of the standing wave pattern were established experimentally and compared with numerical simulations. Fourier analysis along the propagation direction reveals noticeable frequencies both on the experiment and the computation that could be related not only to the guided mode but also to beating phenomena between the coupled waveguides. Finally, light confinement above the slot is directly visualized with a subwavelength resolution and is compared with the expected field distribution.
Lasers, fibres et télécommunications
REE N°1/2012 ◗ 21 LES GRANDS DOSSIERsIntroduction 50 ans apres son invention, et suite a des inno... more REE N°1/2012 ◗ 21 LES GRANDS DOSSIERsIntroduction 50 ans apres son invention, et suite a des innovations conti- nues, le laser reste une brique essentielle, et meme revolution- naire, dans les telecommunica- tions et plus generalement dans les sciences et les technologies de la communication1 2 . Le laser, dispositif issu de la recherche fondamentale3 a trouve tres ra- pidement des applications pour les communications grâce a des pionniers gravitant dans ce domaine. Aujourd’hui, il de- meure le dispositif fondamental de toute technologie des communications, qu’elle soit fibree ou non. Ce dos- sier intitule « lasers, fibres et telecommunications » vise a la fois a faire un point sur l’evolution des reseaux de te- lecommunications optiques et a recueillir les temoigna- ges de grands acteurs qui ont joue un role cle dans cette evolution. Quatre articles presentent ainsi l’etat actuel des telecommunications optiques et un bilan historique de l’evolution des technologies de telecommunications optiques qui ont, grâce a leurs progres incessants, per- mis les progres des reseaux optiques. Deux acteurs de la recherche actuelle commenc
Optics Communications, 2005
Numerical simulations of two-dimensional probe-object system emulating a photon scanning tunnelli... more Numerical simulations of two-dimensional probe-object system emulating a photon scanning tunnelling microscope are presented. R-matrix propagation algorithm incorporated into the differential method was used to achieve an extended capability to rigorously model a realistic system consisting of both a probe and a sample. Influence of the probe tip parameters on image formation in scanning near-field microscopy has been investigated. Coupling of the near-field to a single-mode probe and formation of a guided fundamental mode in a probe were investigated for various probe widths and lengths. The influence of the probe taper shape and apex size on near-field images was studied for single-mode as well as multimode probes. The obtained results allow comparison of simulated images to unperturbed near-field distribution around the object in the absence of a probe and provide an understanding of the degree of perturbation introduced by probe tip in near-field. It is shown that whole taper of probe contributes to image formation, and thus, a realistic model cannot truncate the probe at distance of few wavelengths from the surface, as is done in the most numerical simulations. The developed model has no computational limitations on optical and geometrical parameters of probe and sample and can be used for realistic simulations of various near-field microscope configurations.
Tunable single-mode excitation in multimode fibres
Electronics Letters, 1984
ABSTRACT Mode selection in lasers is used in order to provide high-purity easy-to-implement singl... more ABSTRACT Mode selection in lasers is used in order to provide high-purity easy-to-implement single-mode launching in optical fibres. Mode-to-mode switching automatically maintains centring, scaling and alignment. Application of the principle to selective launching into a weakly multimode fibre (V=4) is demonstrated.
ACS Photonics, Apr 26, 2016
We employ nonlinear autocorrelation measurements to investigate plasmon-assisted hot carrier dyna... more We employ nonlinear autocorrelation measurements to investigate plasmon-assisted hot carrier dynamics generated in optical gold antennas. We demonstrate that surface plasmons enable a nonlinear formation of hot carriers, providing thus a unique lever to optimize the energy distribution and generation efficiency of the photo-excited charges. The temporal response of the carriers' relaxation can be controlled within a range extending from 500 fs to 2.5 ps. By conducting a quantitative analysis of the dynamics, we determine the nonlinear absorption cross-section of individual optical antennas. As such, this work provides strong insights on the understanding of plasmon-induced hot carrier generation, especially in the view of applications where the time response plays a preponderant role.
Optics Express, 2004
The Bloch mode spectrum of surface plasmon polaritons (SPPs) on a finite thickness metal film has... more The Bloch mode spectrum of surface plasmon polaritons (SPPs) on a finite thickness metal film has been analyzed in the regimes of weak and strong coupling between SPP modes on the opposite film interfaces. The SPP mode dispersion and associated field distributions have been studied. The results have been applied to the description of the light transmission through thick and thin periodically structured metal films at oblique incidence. In contrast to normal incidence, all SPP Bloch modes on a grating structure participate in the resonant photon tunnelling leading to the transmission enhancement. However, at the angle of incidence corresponding to the crossing of different symmetry film SPP Bloch modes, the far-field transmission is suppressed despite the enhanced near-field transmission. The combined SPP mode consisting of the two film SPPs having different symmetries that is achieved at the crossing frequency exhibits no radiative losses on a structured surface.
Sample–tip coupling efficiencies of the photon-scanning tunneling microscope
Journal of the Optical Society of America, Dec 1, 1991
ABSTRACT
Bloch Modes Coupling in Photonic Crystal Waveguides
ABSTRACT
Direct Observation and Spectroscopy of Optical Modes in Photonic Crystal Microcavity
Conference on Lasers and Electro-Optics, May 22, 2005
From Measurement to Control of Electromagnetic Waves using a Near-field Scanning Optical Microscope
We show here that the optical bistability of a nonlinear nanoresonator can be efficiently control... more We show here that the optical bistability of a nonlinear nanoresonator can be efficiently controlled by manipulating dynamically the resonance of the optical cavity with a near-field tip. We demonstrate experimentally that the operating regime of the nanocavity can be switched between the monostable and the bistable regimes. Finally, we propose an analytical model which provides a clear understanding of the whole nonlinear opto-mechanical system reported here.
Journal of Microscopy, May 1, 1999
A prism coupling arrangement is used to excite surface plasmons at the surface of a thin silver f... more A prism coupling arrangement is used to excite surface plasmons at the surface of a thin silver film and a photon scanning tunnelling microscope is used to detect the evanescent field above the silver surface. Excitation of the silver/ air mode of interest is performed at l 1 ¼ 632•8 nm using a tightly focused beam, while the control of the tip is effected by exciting a counter-propagating surface plasmon field at a different wavelength, l 2 ¼ 543•5 nm, using an unfocused beam covering a macroscopic area. Propagation of the red surface plasmon is evidenced by an exponential tail extending away from the launch site, but this feature is abruptly truncated if the surface plasmon encounters the edge of the silver film -there is no specularly reflected 'beam'. Importantly, the radiative decay of the surface mode at the film edge is observable only at larger tip-sample separations, emphasizing the importance of accessing the mesoscopic regime.
Numerical study of the tip-sample interaction in the photon scanning tunneling microscope
Optics Communications, May 1, 1996
ABSTRACT
Spectroscopic Study of a Spectrally Sensitized Tabular Grain AgBr Emulsion Using Both AFM and PSTM Techniques
Journal of Imaging Science and Technology, Mar 1, 1998
ABSTRACT
Sub-Wavelength Imaging of Light Confinement and Propagation in Soi Based Photonic Crystal Devices
ABSTRACT A light source is coupled into photonic crystal devices and a near field optical probe i... more ABSTRACT A light source is coupled into photonic crystal devices and a near field optical probe is used to observe the electromagnetic field propagation and distribution at a sub-wavelength scale. Bloch modes are clearly observed.
Numerical study on localized defect modes in two-dimensional triangular photonic crystals
Journal of Applied Physics, 1998
The eigenfrequencies and eigenfunctions of localized defect modes in two-dimensional triangular p... more The eigenfrequencies and eigenfunctions of localized defect modes in two-dimensional triangular photonic crystals composed of circular dielectric rods were calculated by means of the numerical simulation of the radiation process of a virtual oscillating dipole moment. In addition to the excellent agreement between our result and the experimental observation by Smith et al. [J. Opt. Soc. Am. B 10, 314 (1993)], we could evaluate the dependence of the eigenfrequency on the size of the supercell used in the numerical calculation. The result was also compared with that of the plane-wave expansion method.
Applied Physics Letters, Feb 21, 2011
arXiv (Cornell University), Jan 12, 2016
We employ nonlinear autocorrelation measurements to investigate plasmon-assisted hot carrier dyna... more We employ nonlinear autocorrelation measurements to investigate plasmon-assisted hot carrier dynamics generated in optical gold antennas. We demonstrate that surface plasmons enable a nonlinear formation of hot carriers, providing thus a unique lever to optimize the energy distribution and generation efficiency of the photo-excited charges. The temporal response of the carriers' relaxation can be controlled within a range extending from 500 fs to 2.5 ps. By conducting a quantitative analysis of the dynamics, we determine the nonlinear absorption cross-section of individual optical antennas. As such, this work provides strong insights on the understanding of plasmon-induced hot carrier generation, especially in the view of applications where the time response plays a preponderant role.
Physical review, Mar 12, 2002
Nonresonant excitation of surface plasmon polaritons at discontinuities of a gold film is numeric... more Nonresonant excitation of surface plasmon polaritons at discontinuities of a gold film is numerically studied and experimentally observed with scanning near-field optical microscopy. It is shown that surface polaritons can be effectively launched at the edges of a metal film illuminated at an angle of incidence greater than the resonant angle of surface polariton excitation. The electromagnetic near-field distribution over a thin metal film exhibits significantly different features under resonant and nonresonant excitations due to different surface polariton excitation mechanisms. In the latter case the field distribution is determined by the interference of the excitation light and surface polaritons launched on air-metal and glass-metal interfaces. In the former case the interference of surface polariton modes excited on different interfaces of a metal film is dominating. The modulation depths of the respective interference patterns correspond to the efficiency of the intensity conversion of the excitation light at the metal discontinuities into surface polaritons of the order of 0.1-0.01 depending on an angle of incidence.
Bloch mode coupling investigation in silicon-on-insulator W1 photonic crystal waveguide
Proceedings of SPIE, Sep 15, 2004
ABSTRACT
Near-field modal microscopy of subwavelength light confinement in multimode silicon slot waveguides
Applied Physics Letters, Dec 22, 2008
Silicon-on-insulator slot waveguides are studied by scanning near-field optical microscopy. Image... more Silicon-on-insulator slot waveguides are studied by scanning near-field optical microscopy. Images of the standing wave pattern were established experimentally and compared with numerical simulations. Fourier analysis along the propagation direction reveals noticeable frequencies both on the experiment and the computation that could be related not only to the guided mode but also to beating phenomena between the coupled waveguides. Finally, light confinement above the slot is directly visualized with a subwavelength resolution and is compared with the expected field distribution.
Lasers, fibres et télécommunications
REE N°1/2012 ◗ 21 LES GRANDS DOSSIERsIntroduction 50 ans apres son invention, et suite a des inno... more REE N°1/2012 ◗ 21 LES GRANDS DOSSIERsIntroduction 50 ans apres son invention, et suite a des innovations conti- nues, le laser reste une brique essentielle, et meme revolution- naire, dans les telecommunica- tions et plus generalement dans les sciences et les technologies de la communication1 2 . Le laser, dispositif issu de la recherche fondamentale3 a trouve tres ra- pidement des applications pour les communications grâce a des pionniers gravitant dans ce domaine. Aujourd’hui, il de- meure le dispositif fondamental de toute technologie des communications, qu’elle soit fibree ou non. Ce dos- sier intitule « lasers, fibres et telecommunications » vise a la fois a faire un point sur l’evolution des reseaux de te- lecommunications optiques et a recueillir les temoigna- ges de grands acteurs qui ont joue un role cle dans cette evolution. Quatre articles presentent ainsi l’etat actuel des telecommunications optiques et un bilan historique de l’evolution des technologies de telecommunications optiques qui ont, grâce a leurs progres incessants, per- mis les progres des reseaux optiques. Deux acteurs de la recherche actuelle commenc
Optics Communications, 2005
Numerical simulations of two-dimensional probe-object system emulating a photon scanning tunnelli... more Numerical simulations of two-dimensional probe-object system emulating a photon scanning tunnelling microscope are presented. R-matrix propagation algorithm incorporated into the differential method was used to achieve an extended capability to rigorously model a realistic system consisting of both a probe and a sample. Influence of the probe tip parameters on image formation in scanning near-field microscopy has been investigated. Coupling of the near-field to a single-mode probe and formation of a guided fundamental mode in a probe were investigated for various probe widths and lengths. The influence of the probe taper shape and apex size on near-field images was studied for single-mode as well as multimode probes. The obtained results allow comparison of simulated images to unperturbed near-field distribution around the object in the absence of a probe and provide an understanding of the degree of perturbation introduced by probe tip in near-field. It is shown that whole taper of probe contributes to image formation, and thus, a realistic model cannot truncate the probe at distance of few wavelengths from the surface, as is done in the most numerical simulations. The developed model has no computational limitations on optical and geometrical parameters of probe and sample and can be used for realistic simulations of various near-field microscope configurations.
Tunable single-mode excitation in multimode fibres
Electronics Letters, 1984
ABSTRACT Mode selection in lasers is used in order to provide high-purity easy-to-implement singl... more ABSTRACT Mode selection in lasers is used in order to provide high-purity easy-to-implement single-mode launching in optical fibres. Mode-to-mode switching automatically maintains centring, scaling and alignment. Application of the principle to selective launching into a weakly multimode fibre (V=4) is demonstrated.
ACS Photonics, Apr 26, 2016
We employ nonlinear autocorrelation measurements to investigate plasmon-assisted hot carrier dyna... more We employ nonlinear autocorrelation measurements to investigate plasmon-assisted hot carrier dynamics generated in optical gold antennas. We demonstrate that surface plasmons enable a nonlinear formation of hot carriers, providing thus a unique lever to optimize the energy distribution and generation efficiency of the photo-excited charges. The temporal response of the carriers' relaxation can be controlled within a range extending from 500 fs to 2.5 ps. By conducting a quantitative analysis of the dynamics, we determine the nonlinear absorption cross-section of individual optical antennas. As such, this work provides strong insights on the understanding of plasmon-induced hot carrier generation, especially in the view of applications where the time response plays a preponderant role.
Optics Express, 2004
The Bloch mode spectrum of surface plasmon polaritons (SPPs) on a finite thickness metal film has... more The Bloch mode spectrum of surface plasmon polaritons (SPPs) on a finite thickness metal film has been analyzed in the regimes of weak and strong coupling between SPP modes on the opposite film interfaces. The SPP mode dispersion and associated field distributions have been studied. The results have been applied to the description of the light transmission through thick and thin periodically structured metal films at oblique incidence. In contrast to normal incidence, all SPP Bloch modes on a grating structure participate in the resonant photon tunnelling leading to the transmission enhancement. However, at the angle of incidence corresponding to the crossing of different symmetry film SPP Bloch modes, the far-field transmission is suppressed despite the enhanced near-field transmission. The combined SPP mode consisting of the two film SPPs having different symmetries that is achieved at the crossing frequency exhibits no radiative losses on a structured surface.
Sample–tip coupling efficiencies of the photon-scanning tunneling microscope
Journal of the Optical Society of America, Dec 1, 1991
ABSTRACT
Bloch Modes Coupling in Photonic Crystal Waveguides
ABSTRACT
Direct Observation and Spectroscopy of Optical Modes in Photonic Crystal Microcavity
Conference on Lasers and Electro-Optics, May 22, 2005
From Measurement to Control of Electromagnetic Waves using a Near-field Scanning Optical Microscope
We show here that the optical bistability of a nonlinear nanoresonator can be efficiently control... more We show here that the optical bistability of a nonlinear nanoresonator can be efficiently controlled by manipulating dynamically the resonance of the optical cavity with a near-field tip. We demonstrate experimentally that the operating regime of the nanocavity can be switched between the monostable and the bistable regimes. Finally, we propose an analytical model which provides a clear understanding of the whole nonlinear opto-mechanical system reported here.
Journal of Microscopy, May 1, 1999
A prism coupling arrangement is used to excite surface plasmons at the surface of a thin silver f... more A prism coupling arrangement is used to excite surface plasmons at the surface of a thin silver film and a photon scanning tunnelling microscope is used to detect the evanescent field above the silver surface. Excitation of the silver/ air mode of interest is performed at l 1 ¼ 632•8 nm using a tightly focused beam, while the control of the tip is effected by exciting a counter-propagating surface plasmon field at a different wavelength, l 2 ¼ 543•5 nm, using an unfocused beam covering a macroscopic area. Propagation of the red surface plasmon is evidenced by an exponential tail extending away from the launch site, but this feature is abruptly truncated if the surface plasmon encounters the edge of the silver film -there is no specularly reflected 'beam'. Importantly, the radiative decay of the surface mode at the film edge is observable only at larger tip-sample separations, emphasizing the importance of accessing the mesoscopic regime.
Numerical study of the tip-sample interaction in the photon scanning tunneling microscope
Optics Communications, May 1, 1996
ABSTRACT
Spectroscopic Study of a Spectrally Sensitized Tabular Grain AgBr Emulsion Using Both AFM and PSTM Techniques
Journal of Imaging Science and Technology, Mar 1, 1998
ABSTRACT
Sub-Wavelength Imaging of Light Confinement and Propagation in Soi Based Photonic Crystal Devices
ABSTRACT A light source is coupled into photonic crystal devices and a near field optical probe i... more ABSTRACT A light source is coupled into photonic crystal devices and a near field optical probe is used to observe the electromagnetic field propagation and distribution at a sub-wavelength scale. Bloch modes are clearly observed.
Numerical study on localized defect modes in two-dimensional triangular photonic crystals
Journal of Applied Physics, 1998
The eigenfrequencies and eigenfunctions of localized defect modes in two-dimensional triangular p... more The eigenfrequencies and eigenfunctions of localized defect modes in two-dimensional triangular photonic crystals composed of circular dielectric rods were calculated by means of the numerical simulation of the radiation process of a virtual oscillating dipole moment. In addition to the excellent agreement between our result and the experimental observation by Smith et al. [J. Opt. Soc. Am. B 10, 314 (1993)], we could evaluate the dependence of the eigenfrequency on the size of the supercell used in the numerical calculation. The result was also compared with that of the plane-wave expansion method.
Applied Physics Letters, Feb 21, 2011
arXiv (Cornell University), Jan 12, 2016
We employ nonlinear autocorrelation measurements to investigate plasmon-assisted hot carrier dyna... more We employ nonlinear autocorrelation measurements to investigate plasmon-assisted hot carrier dynamics generated in optical gold antennas. We demonstrate that surface plasmons enable a nonlinear formation of hot carriers, providing thus a unique lever to optimize the energy distribution and generation efficiency of the photo-excited charges. The temporal response of the carriers' relaxation can be controlled within a range extending from 500 fs to 2.5 ps. By conducting a quantitative analysis of the dynamics, we determine the nonlinear absorption cross-section of individual optical antennas. As such, this work provides strong insights on the understanding of plasmon-induced hot carrier generation, especially in the view of applications where the time response plays a preponderant role.