Loic Bodiou

Loic Bodiou
Université de Rennes 1 | UR1 · Laboratoire FOTON - Fonctions Optiques pour les Technologies de l'information

About

61
Publications
5,592
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
521
Citations
Additional affiliations
October 2004 - November 2007

Publications

Publications (61)
Article
Full-text available
Porous germanium is a promising material for sensing applications in the mid-infrared wavelength range due to its biocompatibility, large internal surface area, open pores network and widely tunable refractive index, as well as its large spectral transparency window ranging from 2 to 15 μm. Multilayers, such as Bragg reflectors and microcavities, b...
Article
Germanium/Zinc Sulphide (Ge/ZnS) single and multilayers are deposited by ion assisted electron beam deposition on Silicon substrates for applications in the 2-15 µm wavelength region. Refractive indices of Ge and ZnS thin films are extracted from measured reflectance and transmittance spectra. Several types of mid-infrared filters (high-, anti-refl...
Article
Full-text available
Chalcogenide-oxide Bragg reflectors and a 1-D vertical cavity for operation at 1.55 µm were designed and fabricated via radio-frequency sputtering. The Bragg reflectors were made out of repeating layers of Al2O3 and As2Se3, and the cavity was obtained via a Ga5Ge20Sb10S65:Er3+ defect layer. The layers’ properties were assessed via ellipsometry and...
Article
Full-text available
In this work, the fabrication of a porous silicon Bragg reflector and vertical cavity on P+ silicon substrate is investigated for applications in spectroscopic sensing in the mid-infrared (Mid-IR) wavelength range. The complex refractive index of porous silicon layers is measured. Optical vertical devices are then fabricated and characterized by Fo...
Article
By means of finite-difference time-domain (FDTD) simulations, the stationary and dynamic responses of coupled optical microring resonators made with a material exhibiting an instantaneous Kerr nonlinearity are numerically investigated. We compare the results with the coupled-mode theory (CMT) and find good agreement. We demonstrate by integrating M...
Article
Full-text available
This work reports on the properties of luminescent waveguides based on quaternary Ga-Ge-Sb-Se amorphous thin films doped with praseodymium. The waveguides were fabricated via magnetron co-sputtering, followed by inductively coupled plasma reactive ion etching. The initial thin film thickness and optical properties were assessed and the spectroscopi...
Article
A 1 x 2 multimode interferometer beam splitter based on mid-infrared emitting chalcogenides waveguides is designed. This device multiplexes mid-infrared light in two channels whose respective passbands overlap either CO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> or CO absorption bands, res...
Article
Third order optical nonlinear effects relying on the instantaneous Kerr effect are investigated in a straight chalcogenide ridge waveguide. The sample consists of a GeSbSe film deposited on a thermally oxidized silicon substrate. Ridge waveguides were processed using photolithography and dry etching techniques. From a 1.1 cm long integrated GeSbSe...
Article
In this paper, we present a comprehensive model for a CW Raman laser in a silicon-on-insulator (SOI) platform. We validate this model by comparing its output with experimental results from the literature. We then design a 2.232 im Raman laser with an on-chip ring resonator cavity. Numerical analysis of laser characteristics, such as threshold power...
Article
Full-text available
The design of porous silicon (PSi) integrated micro-resonators (MRs) is studied for both surface sensing and homogeneous sensing at 1550 nm to optimize the sensors' sensitivity and limit of detection (LOD) as a function of the porosity, dimensions and propagation losses of PSi ridge waveguides. A model for estimating the different contributions to...
Article
Ce papier présente des exemples de travaux de recherche réalisés au laboratoire Fonctions Optiques pour les Technologies de l’information (Foton UMR-CNRS 6082) par des enseignants chercheurs de l’IUT de Lannion (Université de Rennes 1). Les thématiques développées concernent l’étude d’une part de méthodes de couplage et d’assemblage optique, notamm...
Article
Praseodymium-doped selenide thin films are deposited by radio frequency magnetron sputtering on thermally oxidized silicon wafers and undoped selenide layers. Ridge waveguides are then processed using photolithography and dry etching techniques. Under optical pumping at 1.55 μm, broadband guided mid-infrared photoluminescence is recorded for the fi...
Article
Full-text available
The detection of molecules dissolved in liquid medium can be envisaged by means of an optical integrated sensor operating in middle infrared range. The intended sensor is composed of a cladding and a guiding selenide sputtered layers transparent in middle infrared. Hence, Ge-Sb-Se thin films were selected in view of tailored refractive index contra...
Conference Paper
Porous silicon (PSi) is material which physical and optical properties have been widely studied for biological sensors. Indeed, the wide internal surface of PSi, as well as its biocompatibility have significant advantages for use in the fields of sensors. Moreover, integrated micro-resonators (MRs), by their geometry and operating principle, allow...
Conference Paper
Full-text available
Development of Mid-infrared sensors for the detection of biochemical molecules is a challenge of great importance. Mid-infrared range (4000 – 400 cm-1) contains the absorption bands related to the vibrations of organic molecules (nitrates, hydrocarbons, pesticides, etc.). Chalcogenide glasses are an important class of amorphous materials appropriat...
Article
Full-text available
We demonstrate the interest of expanded beam microlenses (around 55 µm of mode field diameter) to relax positioning tolerances and to decrease reflectance in single mode fiber to fiber interconnexions. We also point out the interest of micro-lenses of very small mode field diameter (around 2 µm) to improve coupling efficiency in specialty fibers an...
Article
A compact amplifier based on chalcogenide Pr3+-doped micro-disk coupled to two ridge waveguides is designed and refined by means of a home-made computer code. The gain G ≈ 7.9 dB is simulated for a Pr3+ concentration of 10 000 ppm, input signal power of −30 dBm at the wavelength 4.7 µm and input pump power of 50 mW at the wavelength 1.55 µm. In the...
Conference Paper
Selenide ridge waveguide based on evanescent field detection was designed, fabricated and optically characterized in mid-infrared (7.7 μm). Results represent the first development step of an integrated optical sensor for pollutant detection in water.
Conference Paper
Full-text available
We demonstrate the interest of expanded beam microlenses (around 55µm of mode field diameter) to relax positioning tolerances and to decrease reflectance in single mode fiber to fiber interconnexions. We also point out the interest of micro-lenses of very small mode field diameter (around 2 µm) to improve coupling efficiency in specialty fibers and...
Article
A selenide integrated platform working in the mid-infrared was designed, fabricated and optically characterized at 7.7 μm. Ge-Sb-Se multilayered structures were deposited by RF magnetron sputtering. Using i-line photolithography and fluorine-based reactive ion etching, ridge waveguides were processed as Y-junction, spiral and S-shape waveguides. Si...
Article
This paper reports the fabrication of luminescent optical rib/ridge waveguides made of erbium doped Ga-Ge-Sb-S films deposited by RF magnetron sputtering. Several fluorescence emissions of Er3+ ions from the visible to the middle infrared spectral domain were clearly observed within the films. The study of the 4I13/2 level lifetime enabled developm...
Article
A micro-sensor based on selenide glasses for evanescent wave detection in mid-infrared spectral range was designed and fabricated. Ge-Sb-Se thin films were successfully deposited by radio-frequency magnetron sputtering. In order to characterize them spectroscopic ellipsometry, atomic force microscopy and contact angle measurements were employed to...
Conference Paper
The mid-infrared (mid-IR) spectral region is of great interest to many areas of science and technology as it contains two important transparency windows (3–5 μm and 8–13 μm) of the Earth’s atmosphere and strong characteristic vibrational transitions displayed by a large number of molecules. Praseodymium ions (Pr3+) feature characteristic transition...
Conference Paper
Racetrack micro-resonator (MR), made from partially or totally oxidized porous silicon (PS) ridge waveguides fabricated with standard photolithography process, is reported. The design and the technological process are described including a study of waveguide dimensions that provide single mode propagation. Scanning electronic microscopy observation...
Article
Full-text available
Three polymethyl methacrylate based copolymers bearing arylvinylpyrimidine chromophores have been synthesized in four steps. Spectral properties of the copolymers have been studied in solution, powder and thin films and compared with the corresponding free chromophores. The copolymers exhibit strong emission solvatochromism and act as polarity sens...
Article
A theoretical study of evanescent optical sensor for multipurpose detection in the Mid-Infrared of gases and pollutants in water is presented in this paper. The opto-geometrical parameters of the transducers – ridge waveguides – have been optimized in order to obtain the highest evanescent power factor for monomodal propagation in the Mid-Infrared....
Conference Paper
Afin de réaliser des capteurs optiques à base de micro-résonateurs très sensibles et facilement intégrables, nous présentons une étude de détection homogène par évanescence sur des micro-résonateurs polymères fabriqués à partir de SU8 pour le cœur et de PMATRIFE pour la gaine inférieure. Aucun superstrat de polymère n’a été déposé sur le micro-réso...
Conference Paper
Le Moyen Infra-Rouge (MIR) est la région spectrale comprise entre 3 et 20 µm. Cette gamme de longueurs d’onde est connue pour contenir des transitions vibrationnelles fondamentales caractéristiques d’espèces moléculaires en phase liquide ou gazeuse. De nombreuses substances telles que le toluène, le méthanol, l’éthanol, l’acétone, le glucose, le di...
Conference Paper
Au cours de la dernière décennie, la technologie des circuits optiques intégrés s'est fortement développée à partir de différents matériaux. Elle commence à atteindre une maturité technologique et commerciale et son évolution peut être comparable à celle précédemment obtenue sur l'évolution de la microélectronique comme nous pouvons le voir sur les...
Article
Full-text available
The fabrication of micro-resonators, made from porous silica ridge waveguides by using an electrochemical etching method of silicon substrate followed by thermal oxidation and then by a standard photolithography process, is reported. The design and fabrication process are described including a study of waveguide dimensions that provide single mode...
Article
Thin films and ridge waveguides based on large-diameter semiconducting single-wall carbon nanotubes (s-SWCNTs) dispersed in a polyfluorene derivative are fabricated and optically characterized. Ridge waveguides are designed with appropriate dimensions for single-mode propagation at 1550 nm. Using multimode ridge waveguides, guided s-SWCNT photolumi...
Conference Paper
Le silicium poreux est un matériau dont les propriétés physiques et optiques ont été largement étudiées pour différentes applications telles que l'optoélectronique [1] ou encore les capteurs chimiques et biologiques [2]. En effet, la large surface interne du silicium poreux ainsi que sa biocompatibilité présentent des atouts importants pour son uti...
Article
Full-text available
A comparative study of the linear and nonlinear optical properties of a novel triphenylamine-pyrimidine alternated oligomer and its corresponding V-shaped quadrupolar monomer is presented. Both chromophores strikingly exhibit the same spectral shape when considering their respective one- and two-photon absorption spectra. This effect was attributed...
Article
Full-text available
Semiconducting carbon nanotubes (CNT) exhibit large nonlinear-and strong quasi-one dimensional excitonic optical properties. Their integration in integrated waveguides could lead to very efficient light-emitting devices or optical signal processing functions. We described the fabrication and optical characterization of hybrid planar waveguides inco...
Article
In the context of optical transmission in the polymer integrated waveguides, transmission losses are a limiting factor for the development of such a technology. In this paper, we analyze the different features that cause optical losses namely intrinsic absorption of the material and light scattering in the bulk. This analysis of optical transmissio...
Conference Paper
Cet article résume le panorama de l'état de l'art des technologies d'optique intégrée maitrisées au laboratoire Foton (Systèmes Photoniques) axé sur l'optique intégrée polymère active et passive, les guides en silicium et silice poreuse pour la réalisation de capteurs biologiques, ainsi que les applications des guides en verres spéciaux étudiés en...
Article
Our study of samples grown in different metalorganic chemical vapor deposition reactors and with different growth conditions reveals that V-pits are always present in (InxAl1−x)N films whatever the layer thickness and the InN content. V-pits are empty inverted pyramids terminating threading dislocations. InN-rich triangular regions are present arou...
Article
Full-text available
Micropowders of cubic boron nitride doped with neodymium are prepared under high-pressure and high-temperature conditions. The phase composition of the micropowders is studied using X-ray diffractometry and X-ray fluorescence analysis. The photoluminescence, photoluminescence excitation spectra, and the life-time of the 4F 3/2 excited state of Nd i...
Article
A comparison is presented between Eu implanted and Eu in situ doped GaN thin films showing that two predominant Eu sites are optically active around 620 nm in both types of samples with below and above bandgap excitation. One of these sites, identified as a Ga substitutional site, is common to both types of Eu doped GaN samples despite the differen...
Article
We report a direct confirmation of the generally proposed rare-earth excitation model in GaN. The intermediate step involving the formation of excitons bound to rare-earth ions prior to the rare-earth excitation is demonstrated. Using a two-color experiment, we show that the erbium photoluminescence decay following a pulsed laser excitation is quen...
Article
Two colour experiments can be used to study the excitation mechanisms of rare-earth ions in rare-earth doped wide-bandgap semiconductors as well as the quenching of their photoluminescence (PL). The combined excitation of Eu3+ implanted GaN samples with a pulsed laser and a CW laser, corresponding, respectively, to a below bandgap excitation and to...
Article
Full-text available
The PhD dissertation is devoted to the understanding of the excitation and quenching mechanisms of rare-earth (Eu3+, Er3+ and Tm3+) doped gallium nitride thin films. Rare-earth doping of GaN thin films results in two different types of incorporation sites for rare-earth ions: "isolated" ions (without any defect in their vicinity) and "rare-earth -...
Article
Two sets of GaN epilayers grown by using the MOCVD technique were implanted with different doses of Tm3+ ions ranging from 1×1015 to 10×1015atcm−2 at various temperatures from 100 to 500°C. After annealing, photoluminescence (PL) and PL excitation (PLE) spectra were recorded at 12K by exciting the samples below and above the bandgap. An analysis of...
Article
In this work we carry out characterization of GaN implanted with Tm and Eu ions by scanning and transmission electron microscopy. Structural investigation is supported by optical measurements. We have investigated samples implanted at room temperature with different energies (150-300 keV) and fluences (1-7 x 10(15) at/cm(2)). High temperature annea...
Article
Europium red photoluminescence (D-5(0)->F-7(2)) in implanted GaN samples is investigated as a function of the annealing temperature. For above bandgap excitation a remarkable increase of the photoluminescence (PL) is observed for samples annealed at 1300 degrees C. Excitation density dependent measurements at 12 K reveal the existence of two major...
Article
Full-text available
Cette thèse porte sur les mécanismes d’excitation et d’émission des couches minces de nitrure de gallium dopées par des ions de terre rare (Eu3+, Er3+ et Tm3+) suite à une excitation optique (photoluminescence) ou électrique (électroluminescence) du matériau semi-conducteur. A l’intérieur du GaN, deux catégories de site d’incorporation d’ions de te...

Network

Cited By

Projects