Person:
Díaz Herrera, Natalia

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First Name
Natalia
Last Name
Díaz Herrera
URI
https://hdl.handle.net/20.500.14352/79985
Affiliation
Universidad Complutense de Madrid
Faculty / Institute
Óptica y Optometría
Department
Óptica
Area
Optica
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2004 - 2009102010 - 201914
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Author: Esteban Martínez, Óscar ×

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Now showing 1 - 10 of 24
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    Uniform-waist tapered optical fibers with double-layer deposition.
    (Second European Workshop On Optical Fibre Sensors: Proceedings, 2004) González Cano, Agustín; Díaz Herrera, Natalia; Navarrete Fernández, María Cruz; Esteban Martínez, Óscar; Bueno Guillén, Francisco Javier
    Novel devices consisting of uniform-waist tapered optical fibers with a double layer (metal plus dielectric) deposition are presented and their properties in terms of optical transmission are studied. Excitation of surface plasmons in the metallic layers is experimentally shown. These devices can be used as basis for new sensors.
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    Sensing properties of asymmetric double-layer-covered tapered fibers
    (Applied Optics, 2004) Bueno Guillén, Francisco Javier; Esteban Martínez, Óscar; Díaz Herrera, Natalia; Navarrete Fernández, María Cruz; González Cano, Agustín
    A novel, to our knowledge, device based on a tapered optical fiber with a double-layer deposition including a metallic media is presented, and its properties are studied. The main novelty of the device consists of the introduction of a dielectric layer, whereas the systems depicted in the literature are simply metal-coated tapered fibers. The presence of the dielectric layer permits one to tune the response of the device to the refractive index of the surrounding medium. We have proved the suitability of this scheme for refractive-index sensing by depicting two measurement modes, namely, total power attenuation and spectral transmittance.
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    Plasmonic sensor based on tapered optical fibers and magnetic fluids for measuring magnetic fields
    (Sensors and actuators A - Physical, 2017) Rodriguez Schwendtner, E.; Díaz Herrera, Natalia; Navarrete Fernández, María Cruz; González Cano, Agustín; Esteban Martínez, Óscar
    We present a new sensor based on the combination of Surface Plasmon Resonance (SPR) with magneto-refractive materials. We use doubly-deposited uniform-waist tapered optical fibers (DLUWTs), that have shown their good performance and versatility as refractometers, and magnetic fluids as transducers to measure magnetic fields in an all-optical-fiber configuration. We experimentally show the feasibility of our approach, by demonstrating the physical principle of the device and characterizing the performance of the sensors, which show very good sensitivity and resolution. In this way, we propose a new field of development for SPR optical fiber sensors to extend the field of application of the plasmonics-based technologies.
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    Extension of Surface Plasmon Resonance in fiber optic sensors into the visible region
    (Fifth European Workshop On Optical Fibre Sensors, 2013) Navarrete Fernández, María Cruz; Díaz Herrera, Natalia; González Cano, Agustín; Esteban Martínez, Óscar
    In this work we experimentally show how the technology of surface plasmon resonance (SPR) in doubly deposited uniform-waist tapered optical fiber sensors (DLUWTs) can be extended into the visible region (around 520 nm) by changing the thicknesses of the deposited layers. In this way, by using DLUWTs we can cover, in an easy and versatile way, a total wavelength range over 1000 nm wide, having shown in the past how this same kind of sensors can be usable in the communication band. The possibilities of fiber sensors can then be applied to the region of visible wavelengths, which is very interesting from the biological point of view.
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    Microfiber as light source for exciting fluorescence in a polymer optical fiber
    (Sensors and Actuators B - Chemical, 2016) Rodriguez Schwendtner, E.; Navarrete Fernández, María Cruz; Díaz Herrera, Natalia; Esteban Martínez, Óscar; González Cano, Agustín
    We present a new technique for exciting and collecting fluorescence with all-fiber devices, consisting of two different tapered fibers, a microfiber used as illuminating source and a polymer optical fiber where a fluorophore has been deposited and where the fluorescence takes place. We depict the fabrication of the device, characterize its performance and show the feasibility of our approach, the good performance obtained and the possibility of using the flexibility of the illuminating fiber to increase this performance and the compactness of the device.
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    Improved performance of SPR sensors by a chemical etching of tapered optical fibers
    (Optics and Lassers in Engineering, 2011) Díaz Herrera, Natalia; Esteban Martínez, Óscar; Navarrete Fernández, María Cruz; González Cano, Agustín; Benito Peña, María Elena; Orellana Moraleda, Guillermo
    We present the results of a chemical attack on the optical fiber surface previous to the deposition of the double layer (metal plus dielectric) in Double-layer uniform-waist tapered fibers (DLUWTs) used for the development of SPR sensors. It is shown how this simple chemical treatment increases the roughness of the surface and permits improvement of the stability of the deposits and the general performance of the sensors. The obtained devices are robust and very compact, their sensitivity is good and repeatability of the measurements is remarkably increased. The procedure can be useful for any fiber-optic sensor.
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    DL-UWTs: novel devices for chemical and biological sensing
    (Third European Workshop on Optical Fibre Sensors, 2007) González Cano, Agustín; Díaz Herrera, Natalia; Navarrete Fernández, María Cruz; Esteban Martínez, Óscar
    Although many optical fiber sensors have been proposed for chemical, environmental or biological measurements, it seems that the potential of this kind of devices has not been fully exploited. In this paper we discuss the possibilities of doubly-deposited uniform-waist tapered fibers (DL-UWTs) for the development of new sensors that can become a new standard in the field of Surface Plasmon Resonance (SPR) based sensors and contribute to the extension of the range of application of fiber technology to the mentioned fields. We also compare different configuration and evaluate some relevant features of DL-UWTs, as the possibility of fully independence of polarization or the excitation of multiple plasmons.
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    A fibre-optic temperature sensor based on the deposition of a thermochromic material on an adiabatic taper
    (Measurement Science and Technology, 2004) Díaz Herrera, Natalia; Navarrete Fernández, María Cruz; Esteban Martínez, Óscar; González Cano, Agustín
    A fibre-optic sensor has been developed for the measurement of temperature, especially of liquids. The device is conceived as part of an all-optical CTD probe for the control of the physical parameters of a marine medium. The dependence on temperature of the optical properties (specifically, absorbance) of a thermochromic material, namely lophine (2,4,5-triphenylimidazole), is the basis of the sensor. The sensor presents some significant differences with respect to other similar sensors proposed in the literature: the use of adiabatic, long, tapered optical fibres with adjustable geometric parameters; the use of LED illumination in the 800 nm range; improvements in the deposition technique, etc. The sensors show a linear behaviour over the desired temperature range, and their sensitivity is high. Also, the dependence of the response of the sensor with variations of the geometry of the tapers is discussed. Specifically, we have performed measurements with different diameters of the taper waist, and we show the dependence of the slope of the response curve with that parameter.
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    Surface plasmon resonance sensors based on uniform-waist tapered fibers in a reflective configuration
    (Applied Optics, 2006) Esteban Martínez, Óscar; Díaz Herrera, Natalia; Navarrete Fernández, María Cruz; González Cano, Agustín
    We present a configuration for surface plasmon resonance sensors based on uniform-waist tapered optical fibers and reflective elements. Once the fiber is tapered fulfilling the adiabatic criterion, a multilayer including a metallic medium is asymmetrically deposited on the uniform waist of the fiber. This feature provides the resonant excitation of multiple surface plasma waves. In addition, a mirror is produced at the fiber tip by a chemical Tollens reaction. In this way, the sensor operates in a reflective mode, more convenient for dip probes. When these sensors are spectrally interrogated, a high sensitivity of 10^4 refractive index units per nanometer is attained. These devices can be advantageously used for any kind of chemical sensing and biosensing.
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    Selectivity of SPR fiber sensors in absorptive media: An experimental evaluation
    (Sensors and Actuators B - Chemical, 2011) Navarrete Fernández, María Cruz; Díaz Herrera, Natalia; González Cano, Agustín; Esteban Martínez, Óscar; Leite, Ivo
    Conventional surface plasmon resonance (SPR) fiber sensors show selective behavior when resonance wavelengths are tuned to absorption peaks of the surrounding medium, as it is experimentally shown and evaluated in this paper by using a doubly-deposited uniform-waist tapered optical fiber (DLUWT) and a dye as a test material. This behavior is clearly distinguishable from the usual response to nonabsorbing media and can be used to develop a new concept of SPR transducers. At the same time, the obtained results, which are in accordance with the theoretical predictions permit to increase the basic knowledge on surface plasma waves excitation in optical fibers.