Search results for "photonics"
showing 10 items of 802 documents
Design and Implementation of Density Sensor for Liquids Using Fiber Bragg Grating Sensor
2022
In this paper, an optical fiber sensor based density sensor is proposed and demonstrated experimentally. The sensor is formed by fiber Bragg grating (FBG) sensor. The proposed sensor design is very simple and versatile for density measurements of liquids. The FBG strain sensor has one end mounted to a 3D printed rigid support, and the other end connected to a 3D manufactured clamp in this sensor design. A metal ball is suspended from this clamp by a non-stretchable cord. When it is completely immersed in liquid, the liquid buoyancy force acts on it. As a result, the strain in FBG varies depending on the force applied to the ball. This results in a wavelength shift in the FBG sensor. The pro…
Abrupt-tapered fiber filter arrangement for a switchable multi-wavelength and tunable Tm-doped fiber laser.
2018
A switchable and tunable multi-wavelength Tm-doped fiber laser is successfully demonstrated using a filter constructed with two tapered fiber elements in the cavity. The proposed system design uses a low-cost simple filter that allows stable dual, triple, quadruple, and quintuple-wavelength emission operation in the region around 1.9 μm. In the dual wavelength regime, the laser is capable of independently tuning each wavelength. For switching and tuning, a curvature is applied to the tapered fibers.
Signal Amplification in CsPbBr3 Nanoparticle-Doped Photonic Crystal Fibers
2019
Nanoparticles (NPs) have been proved for various photonic and optoelectronic applications with superior performance. Doping holey-fibers with colloidal NPs is an idea with precedents in the optical literature. For example, CdZnS/ZnS core-shell quantum dots (QDs) based lasers at visible wavelengths [1, 2]; and PbS QDs doped fiber amplifiers operating at telecommunication wavelengths [3]. In this paper we harness the potential of photonic crystal fibers (PCFs) doped with chemically synthesized CsPbBr 3 Colloidal-NPs [4] to demonstrate gain functionalities in all-fiber optical microdevices.
Large Photonic Films by Crystallization on Fluid Substrates
2002
Cracks, which appear due to shrinkage during drying of artificial opaline films, strongly limit the use of these materials. Crystallization on fluid substrates (liquid metals) is a way to circumvent this problem. By this method it is possible to prepare crack-free three-dimensional “monocrystals” with a very low defect density and the size in millimeters.
Exploring 10 Gb/s transmissions in Titanium dioxide based waveguides at 1.55 pm and 2.0 pm
2017
Exploring new spectral bands for optical transmission is one of the solutions to support the increasingly demand of data traffic. The recent development of dedicated hollow-core photonic bandgap fibers [1], associated to the emergence of thulium doped fiber amplifiers [2] has recently focused the attention further in the infrared, and more specifically around 2 μm. Regarding integrated photonics, it becomes therefore interesting to find a suitable platform to operate at 2 μm as well as in the other more conventional spectral bands (going from 800 nm to 1550 nm). Here, we propose titanium dioxide (TiO 2 ) as a good candidate for integrated waveguide photonics and demonstrate, for the first t…
SUBWAVELENGTH OPTICAL DEVICES FOR NANOMETER SCALE APPLICATIONS
2002
Recent progress in near-field optics instrumentation led to a new class of subwavelength optical experiments in which it is intended to use either the optical tunnel effect (OTE) or the lower mode based transmission (LMBT) in order to control the optical transfer between several delocalized detection or injection centers. This paper presents a panel of new theoretical and experimental results computed or observed near various dielectric or metallic patterns, linear, curved, or dashed, integrated in coplanar geometry. In particular, we demonstrate, how an efficient control of light evanescent waves can allow structures of subwavelength cross sections to be addressed.
Performance of sensl C-Series SiPM with high photoelectron resolution at cryogenic temperatures
2016
The C-Series of silicon photomultipliers (SiPM) from SensL provides devices with a fast response and high performance at low cost. The device's ability to detect light at temperatures of liquid nitrogen (77K) and liquid helium (4 K) with high photoelectron resolution was demonstrated. Results include relative photon detection efficiency (PDE), gain, microcell capacitance, and cross-talk probability at different over-voltages, both at room and at cryogenic temperatures. At 77K the SiPM demonstrated significantly improved operating characteristics while at 4K the observed increase in break-down voltage, the reduction of PDE by a factor of 2-3, and the extensively dropped microcell capacitance…
High Quality Factor Silicon Membrane Metasurface for Intensity-Based Refractive Index Sensing
2021
We propose a new sensing device based on all-optical nano-objects placed in a suspended periodic array. We demonstrate that the intensity-based sensing mechanism can measure environment refractive index change of the order of 1.8×10−6, which is close to record efficiencies in plasmonic devices.
Two-Color Single Hybrid Plasmonic Nanoemitters with Real Time Switchable Dominant Emission Wavelength
2015
International audience; We demonstrate two-color nanoemitters that enable the selection of the dominant emitting wavelength by varying the polarization of excitation light. The nanoemitters were fabricated via surface plasmon-triggered two-photon polymerization. By using two polymerizable solutions with different quantum dots, emitters of different colors can be positioned selectively in different orientations in the close vicinity of the metal nanoparticles. The dominant emission wavelength of the metal/polymer anisotropic hybrid nanoemitter thus can be selected by altering the incident polarization.
Polymer based tuneable photonic crystals
2007
We report on the fabrication and characterization of photonic crystal slab waveguide resonators which contain a nanostructured second-order nonlinear optical polymer. The combination of a photonic crystal resonator realized in a second-order nonlinear optical polymer allowed the detection of electro-optical modulation of light with a sub-1-V sensitivity. Furthermore we report on the synthesis of novel nonlinear optical polymers with large second-order hyperpolarizability and improved glass transition temperature. The polymer slab waveguide is micro patterned by means of electron-beam lithography and reactive ion etching. The photonic crystal slab-based resonator consisted of a square lattic…