Search results for "photonics"

Spatially resolved photonic transfer through mesoscopic heterowires

2002

We report spatially resolved observations of light wave propagation along high refraction index dielectric heterowires lying on a transparent substrate. The heterowires are made of linear chains of closely packed mesoscopic particles. The optical excitation of these heterowires is performed through channel waveguides featuring submicrometer transverse cross sections. Both numerical simulations and near-field optical images, recorded with a photon scanning tunneling microscope, agree to show that, at visible frequencies, tuning the periodicity of the heterowires controls the propagation length within a range of several micrometers.

Recess photomask contact lithography and the fabrication of coupled silicon photonic and plasmonic waveguide switches

2015

Display Omitted A lithography technique capable of printing submicron-sized features inside deep cavities is presented.A so-called recess photomask adapted to the wafer's topography is employed.Based on a standard mask aligner, Recess Photomask Contact Lithography has moderate cost.Its efficiency for a photonic/plasmonic switch application was demonstrated experimentally.The technique is extensible to any design and to wafers with multiple level recesses. A novel lithographic method is presented, based on the use of a mask aligner in the contact mode with a modified photomask, the so-called recess photomask; its goal is the printing of submicron-sized patterns into deep cavities of a chip, …

Nanophotonics and Optical MEMS: Building All-Optical Satellites

2006

Theory of Near‐field Optical Imaging with a Single Molecule as Light Source

2002

Scanning near-field optical microscopes (SNOM) illuminate a sample in the very near-field using a nanometer sized tip. Ideally, the light source should be point-like and many efforts have been made to optimize tip efficiency (see, for example, the article of Heimel et al in this issue). Very recently, Sandoghdar et al have realized a molecular probe tip in which a terrylene molecule inserted in a paraterphenyl microcrystal is attached at the extremity of the probe tip [1]. The excited molecule behaves as a point-like light source which is raster scanned over an aluminium patterned structure. We propose here an analysis of this experiment based on the field-susceptibility formalism (also cal…

Polymer-metal plasmonic waveguide : passive and active components for integrated photonics

2009

Dielectric loaded surface plasmon polariton waveguides (DLSPPWs) enable transmission at a sub-wavelength scale of both electrical and plasmonic (optical waves at the interface between a metal and a dielectric) signals in the same circuitry. Moreover, the use of a polymer as the dielectric load enables the functionalization of DLSPPWs. Therefore, this configuration is of great interest for integrated photonic applications. However, DLSPPWs suffer strong losses due to dissipation into the metal film. We address here the possibility of compensating the losses using a configuration analogous to an optical amplifier. We first set theoretical (effective index model), numerical (differential metho…

Polarization Modulation Instability in All-Normal Dispersion Microstructured Optical Fibers With Quasi-Continuous Pump

2019

We report the experimental observation of the polarization modulation instability (PMI) effect in all-normal dispersion (ANDi) microstructured optical fibers (MOFs) with quasi-continuous pumping. The small unintentional birefringence (~10-5), that any realistic non-polarization maintaining MOF exhibits, contributes to this nonlinear effect. PMI can produce two sidebands whose polarization state is orthogonal to the polarization of the pump. In this work, only one type of PMI process is observed, i.e., when the pump is polarized along the slow axis of the fiber and sidebands are generated in the fast axis mode. This PMI process was studied experimentally in two ANDi fibers with different dis…

"Photonic lantern" spectral filters in multi-core fibre

2012

Fiber Bragg gratings are written across all 120 single-mode cores of a multi-core optical Fiber. The Fiber is interfaced to multimode ports by tapering it within a depressed-index glass jacket. The result is a compact multimode "photonic lantern" filter with astrophotonic applications. The tapered structure is also an effective mode scrambler.

Analysis of Fiber Inhomogeneity Using Time-Resolved Acousto-Optic Interaction

2013

Workshop on Specialty Optical Fibers and their Applications 2013, Sigtuna Sweden, 28–30 August 2013

Polarization mode dispersion and vectorial modulational instability in air silica microstructure fiber

2002

The birefringence of an air-silica microstructure fiber has been studied by measurement of the fiber polarization mode dispersion (PMD) over the wavelength range 545-640 nm. The experimental results are shown to be in good agreement with vectorial numerical calculations, assuming an elliptical core with an eccentricity of 7%. We also report controlled experiments studying nonlinear vectorial modulation instability in the fiber, yielding 3.9-THz modulational instability sideband shifts that are in good agreement with theoretical predictions based on the calculated fiber dispersion and PMD characteristics.

Imaging quality of multifocal intraocular lenses: automated assessment setup

2012

[EN] Purpose: A new technique for the assessment of the optical quality of multifocal intraocular lenses (MIOLs) under monochromatic and polychromatic illumination is presented. Methods: The system provides, in a totally automated procedure, the modulation transfer function (MTF) of the lens under test for different axial positions of the object. The artificial eye admits different artificial corneas, to optimise the axial resolution in the sampling of the MTF of the MIOL under test, and different pupils, to test the dependence of the optical performance of the MIOL on the eye pupil diameter. Results: The performance and sensitivity of the apparatus is tested with different commercial MIOLs…