Search results for "optoelectronic"
showing 10 items of 2328 documents
Purcell factor for 3D- dipolar emitter coupling to 2D- plasmonic waveguides
2011
We theoretically investigate spontaneous emission of a quantum (3D) dipolar emitter located near a (2D) plasmonic waveguide of arbitrary form. The channels into which emitter couples (plasmon, scattering, electron-hole pairs creation) are well identified.
Conditions for waveguide decoupling in square-lattice photonic crystals
2004
We study coupling and decoupling of parallel waveguides in two-dimensional square-lattice photonic crystals. We show that the waveguide coupling is prohibited at some wavelengths when there is an odd number of rows between the waveguides. In contrast, decoupling does not take place when there is even number of rows between the waveguides. Decoupling can be used to avoid cross talk between adjacent waveguides.
Kerr Optical Frequency Combs With Multi-FSR Mode Spacing in Silica Microspheres
2021
We experimentally demonstrate Kerr optical frequency combs (OFCs) with mode spacing of 1, 2, 3, 5, 6, and 8 free spectral ranges (FSRs) corresponding to 0.4, 0.8, 1.2, 2, 2.4, and 3.2 THz, respectively, in silica microspheres pumped by CW C-band lasers in the anomalous dispersion range. Experimental realizations are based on using standard telecom equipment and components such as SMF-28e fiber for producing microspheres and fiber tapers for pump coupling and OFC outcoupling. Numerical simulation is performed to support the experimental results and explain the observed spectral asymmetry in OFCs by the influence of the 3rd-order dispersion.
Purcell-enhancement of the radiative PL decay in perylenediimides by coupling with silver nanoparticles into waveguide modes
2017
In this work, an interesting approach to enhance the coupling between excitons and plasmons is proposed by integrating highly luminescent perylenediimides (PDIs) and Ag metal nanoparticles (MNPs) in the core of a multilayer dielectric waveguide. The combination of the weak plasmonic coupling and the high scattering of MNPs gives rise to a significant improvement of the PDI photoluminescence and Purcell factor (PF) in forward-scattering geometry. Furthermore, when the PDI-MNP system is used as the core of a multilayer waveguide, a Purcell factor enhancement larger than 10 is observed, which is explained by an increase in the exciton-plasmon coupling under the light confinement in the wavegui…
Aluminum Plasmonics: Fabrication and Characterization of Broadly Tunable Plasmonic Surfaces for Plasmon Molecule Strong-Coupling and Fluorescence Enh…
2018
Our work based on previous studies [1, 2] confirms, that simple aluminum nanostructures can be utilized as effective plasmonic resonators over a broad range of frequencies and wavelengths. The nanostructured surfaces, fabricated by electron-beam lithography demonstrated relatively narrow-band resonances and are suitable for various plasmonic applications ranging from metal enhanced fluorescence to strong-coupling [1, 2, 3, 4, 5] experiments. We represent data for molecule-plasmon coupling near the strong coupling limit and demonstrate that these aluminum structures do act as fluorescence increasing substrates. In this work, we used two different types of dyes. We studied the narrow band j-a…
Regular Horizontal Patterning on Colloidal Crystals Produced by Vertical Deposition
2009
Colloidal particles have proved to be a suitable precursor to the formation of nanoscaled materials. More explicitly, they are a suitable way to create photonic band gap materials in 3D. Several methods have been developed to assemble colloidal multilayer systems, and have yielded various levels of success. The vertical deposition method has shown itself to be one of the best in terms of time, control of the final product, crystal size and homogeneity. Despite this, the resulting crystals often present point defects, dislocations, cracks and polycrystallinity, as well as a horizontal modulation of film thickness. These defects compromise the possible utilities of the crystals. The study of …
Carrier Transport in GaAs Nanowires Using Surface Acoustic Waves
2012
ABSTRACTThe oscillating piezoelectric field of a surface acoustic wave (SAW) is employed to transport photoexcited electrons and holes in GaAs nanowires (NWs) transferred to a SAW beam line on a LiNbO3 crystal. We show that carriers generated in the NW by a focused light spot can be acoustically transported to a second location, where they recombine emitting short light pulses. The results presented here demonstrate the high-frequency manipulation of carriers in NWs without the use of electrical contacts, which opens new perspectives for applications in opto-electronic devices operating at GHz frequencies.
Analog Photonic Fractional Signal Processing
2018
Fil: Cuadrado Laborde, Christian. Universidad de Valencia. Instituto Universitario de Ciencia de los Materiales; España Fil: Cuadrado Laborde, Christian. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Cuadrado Laborde, Christian. Pontificia Universidad Católica Argentina. Facultad de Química e Ingeniería del Rosario; Argentina Fil: Poveda-Wong, Luis. Universidad de Valencia. Instituto Universitario de Ciencia de los Materiales; España Fil: Carrascosa, Antonio. Universidad de Valencia. Instituto Universitario de Ciencia de los Materiales ; España Fil: Diez, Antonio. Universidad de Valencia. Instituto Universitario de Ciencia de los Materiales; España Fil: Cruz, Jo…
Cylindrical Cuvette Light Refraction Measurements Technology to Analyse Biomedical Liquids
2015
Compact device of high sensitivity for measurement of the refractive indices for both stationary and flowing liquids has been developed. This device can be used to analyse a variety of biomedical liquids: urine, serum protein. The refractive index (RI) is determined by measuring the deviation of a laser beam passing through a cylindrical cuvette containing the test liquid. In order to significantly improve the resolution and stability of RI measurements, the repeated reflections and refractions of the light beam travelling through the cylindrical cuvette are employed.
A DC and small signal AC model for organic thin film transistors including contact effects and non quasi static regime
2017
Abstract We present a compact model for the DC and small signal AC analysis of Organic Thin Film Transistors (OTFTs). The DC part of the model assumes that the electrical current injected in the OTFT is limited by the presence of a metal/organic semiconductor junction that, at source, acts as a reverse biased Schottky junction. By including this junction, modeled as a reverse biased gated diode at source, the DC model is able to reproduce the scaling of the electrical characteristics even for short channel devices. The small signal AC part of the model uses a transmission line approach in order to compute the impedances of the channel and parasitic regions of the device. The overlap capacit…