Open Access
D-shape optical fiber pH sensor based on lossy mode resonances (LMRs)
(IEEE, 2016-01-07) Zubiate Orzanco, Pablo; Ruiz Zamarreño, Carlos; Del Villar, Ignacio; Matías Maestro, Ignacio; Arregui San Martín, Francisco Javier; Ingeniería Eléctrica, Electrónica y de Comunicación; Ingeniaritza Elektrikoa, Elektronikoa eta Telekomunikazio Ingeniaritza
The fabrication and characterization of an optical fiber pH sensor based on Lossy Mode Resonances (LMRs) is presented. PAH/PAA polymeric thin-films fabricated onto side-polished D-shaped optical fibers are used as LMR supporting coatings. The thickness of PAH/PAA coatings can be modified as a function of the external medium pH. As a consequence of this variation, the effective refractive index of the structure will change, producing a shift of the LMR. The fabricated sensor has been used to measure pH from 4.0 to 5.0. This pH sensor showed a sensitivity of 101.3 nm per pH unit, which means a resolution of ~6×10-4 pH units by using a conventional communications Optical Spectrum Analyzer (OSA), which is an improvement over commercial pH sensors.
Open Access
Optical fiber vacuum sensor based on etched SMS structure and PDMS coating
(IEEE, 2020) Ascorbe Muruzabal, Joaquín; Fuentes Lorenzo, Omar; Arregui San Martín, Francisco Javier; Matías Maestro, Ignacio; Corres Sanz, Jesús María; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren; Institute of Smart Cities - ISC; Ingeniería Eléctrica, Electrónica y de Comunicación
In this work, an optical fiber vacuum sensor based on a single-mode multimode single-mode (SMS) structure coated with polydimethylsiloxane (PDMS) is studied. The SMS structure generates an interferometric pattern based on multimode interference. The structure is dip-coated with a layer of PDMS, whose optical properties change when it is subjected to varying vacuum pressure. Different strategies are applied in an attempt to improve the final performance of the sensor, such as decreasing the diameter of the fiber and modifying the properties of the coating by modifying the proportion of solvent. Decreasing the diameter of the optical fiber and using toluene as a solvent are both proved to be successful strategies for increasing the sensitivity of the sensor. The devices are studied in the 1×10-3–10 mbar range with a maximum wavelength shift of 12 nm, leading to a maximum sensitivity of 35 nm/mbar. The simplicity of the fabrication process, which can be applied to more sensitive structures, suggests that PDMS may be a good choice for the development of optical fiber vacuum sensors.
Open Access
D-shape optical fiber refractometer based on TM and TE lossy mode resonances
(SPIE, 2014) Zubiate Orzanco, Pablo; Ruiz Zamarreño, Carlos; Del Villar, Ignacio; Matías Maestro, Ignacio; Arregui San Martín, Francisco Javier; Ingeniería Eléctrica, Electrónica y de Comunicación; Ingeniaritza Elektrikoa, Elektronikoa eta Telekomunikazio Ingeniaritza
The fabrication and characterization of an optical fiber refractometer based on Lossy Mode Resonances (LMR) is presented. TiO2/ poly (sodium 4-styrenesulfonate) coatings deposited on side-polished D-shaped optical fibers are used as LMR supporting coatings. LMRs are sensitive to the external medium refractive index and D-shaped optical fibers enable the observation of TE and TM LMR polarizations. These refractometers based on TE and TM LMR showed an average sensitivity of 2737 nm/RIU and 2893 nm/RIU respectively for a surrounding medium refractive index (SMRI) range from 1.35 to 1.41.
Open Access
Fiber-optic immunosensor based on lossy mode resonances induced by indium tin oxide thin-films
(IEEE, 2017) Socorro Leránoz, Abián Bentor; Del Villar, Ignacio; Corres Sanz, Jesús María; Arregui San Martín, Francisco Javier; Matías Maestro, Ignacio; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa; Institute of Smart Cities - ISC
A novel immunosensor based on lossy mode resonances (LMRs) induced in optical fibers is developed in this contribution. Indium tin oxide (ITO) is sputtered on the optical substrate to generate an LMR in the transmission spectrum. Type G immunoglobulins (IgGs) are then attached to the ITO-coated fiber using (3-glycidyloxypropyl)trimethoxysilane (GPTMS). A phosphate buffer saline solution containing anti-IgGs is used to detect the biological reactions. The presented device is capable of detecting anti-IgG concentrations up to 10 nM. These results will permit the fabrication of biosensors based on a covalent attachment of bioreceptors over an LMR inducing thin-film.
Open Access
Optical fiber sensors based on indium tin oxide surface plasmon resonance supporting coatings
(SPIE, 2009-10-05) Ruiz Zamarreño, Carlos; Hernáez Sáenz de Zaitigui, Miguel; Matías Maestro, Ignacio; Arregui San Martín, Francisco Javier; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa
In this work, surface plasmon resonance (SPR) based optical fiber sensors are revisited by using a transparent conductive coating, Indium Tin Oxide in our case, as the SPR supporting layer. The utilization of these coatings shifts the plasmon resonance band to the infra-red region and allows the tunability of the SPR wavelength by adjusting the film fabrication parameters. Here, we study the fabrication process of these novel devices and characterize their response to variations in the refractive index of the external medium opening the door to a wide range of applications.
Open Access
Humidity sensor based on silver nanopartlcles embedded in a polymeric coating
(Sciendo, 2012) Rivero Fuente, Pedro J.; Urrutia Azcona, Aitor; Goicoechea Fernández, Javier; Arregui San Martín, Francisco Javier; Matías Maestro, Ignacio; Ingeniería; Ingeniaritza; Ingeniería Eléctrica, Electrónica y de Comunicación; Ingeniaritza Elektrikoa, Elektronikoa eta Telekomunikazio Ingeniaritza; Institute for Advanced Materials and Mathematics - INAMAT2; Institute of Smart Cities - ISC
In this work, it is presented a novel optical fiber humidity sensor based on silver nanoparticle-loaded polymeric coatings built onto an optical fiber core. The polymeric film was fabricated using the Layer-by-Layer assembly technique. The silver nanoparticles (Ag NPs) were characterized using transmission electron microscopy (TEM and UV-VIS spectroscopy. A Localized Surface Plasmon Resonance (LSPR) attenuation band is observed when the thickness of the coating increases, and showed a very good sensitivity to Relative Humidity (RH) variations, suitable for high performance applications such as human breathing monitoring.
Open Access
Is there a frontier in sensitivity with lossy mode resonance (LMR) based refractometers?
(Nature Publishing Group, 2017) Ozcariz Celaya, Aritz; Ruiz Zamarreño, Carlos; Zubiate Orzanco, Pablo; Arregui San Martín, Francisco Javier; Ingeniaritza Elektrikoa eta Elektronikoa; Institute of Smart Cities - ISC; Ingeniería Eléctrica y Electrónica; Gobierno de Navarra / Nafarroako Gobernua; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa
A tin dioxide thin layer has been studied in order to improve the sensitivity of lossy mode resonances (LMR) based sensors. The effects of the thin film thickness and the polarization of light in a SnO2 coated D-shaped single mode optical fiber have been evaluated. The optimization of such parameters in the fabrication of refractometers have led to an unprecedented sensitivity of over one million nanometers per refractive index unit (RIU), which means a sensitivity below 10^(−9) RIU with a pm resolution detector. This achievement is a milestone for the development of new high sensitivity devices and opens the door to new industrial applications, such as gear oil degradation, or biomedical devices where previous devices could not provide enough sensitivity.
Open Access
Optical fiber vacuum sensor based on modal interferometer and PDMS coating
(IEEE, 2019) Ascorbe Muruzabal, Joaquín; Fuentes Lorenzo, Omar; Corres Sanz, Jesús María; Arregui San Martín, Francisco Javier; Matías Maestro, Ignacio; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren; Institute of Smart Cities - ISC; Ingeniería Eléctrica, Electrónica y de Comunicación
This work studies the behavior of polydimethylsiloxane (PDMS) as a transducer for optical vacuum pressure measurements. The optical structure chosen for this device is a modal interferometer achieved by splicing a coreless multimode optical fiber between two single mode fibers. Then, an etching process is applied to the obtained device, in order to decrease the diameter of the fiber and increase the sensitivity. Finally, the fiber is coated by dip-coating with a layer of PDMS, which changes its volume with pressure changes. The device has been studied in the 1x10(-3) mbar to 10 mbar range with a wavelength shift of 4 nm. A maximum sensitivity of 35 nm/mbar was obtained. The simple fabrication process, which can be applied to more sensitive structures, suggest that PDMS can be a good choice for the development of optical fiber vacuum sensors.
Open Access
SnO2 based optical fiber refractometers
(SPIE, 2012) Sánchez Zábal, Pedro; Ruiz Zamarreño, Carlos; Hernáez Sáenz de Zaitigui, Miguel; Del Villar, Ignacio; Matías Maestro, Ignacio; Arregui San Martín, Francisco Javier; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa; Gobierno de Navarra / Nafarroako Gobernua
In this work, the fabrication and characterization of refractometers based on lossy mode resonances (LMR) is presented. Tin dioxide (SnO2) films deposited on optical fibers are used as the LMR supporting coatings. These resonances shift to the red as a function of the external refractive index, enabling the fabrication of robust and highly reproducible wavelength-based optical fiber refractometers. The obtained SnO2-based refractometer shows an average sensitivity of 7198 nm/refractive index unit (RIU) in the range 1.333-1.420 RIU.
Open Access
Aluminum doped zinc oxide (AZO) coated optical fiber LMR refractometers. An experimental demonstration
(Elsevier, 2019) Ozcariz Celaya, Aritz; Piña-Azamar, Dafne A.; Ruiz Zamarreño, Carlos; Domínguez Cruz, René; Arregui San Martín, Francisco Javier; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren; Institute of Smart Cities - ISC; Ingeniería Eléctrica, Electrónica y de Comunicación; Gobierno de Navarra / Nafarroako Gobernua
This work presents the experimental demonstration of lossy mode resonance generation by means of aluminum doped zinc oxide thin-films. The use of such material may allow to optimize the performance of LMR-based sensors, obtaining good sensitivity at lower costs than other overlays, such as those including indium. The refractometric response of the fabricated devices is explored in different spectral regions. One refractometer working in the near infrared region was fabricated, obtaining a sensitivity of 2280 nm/RIU. A second refractometer working in the visible light spectrum was also fabricated. This second device allows to observe rough refractive index variations with the naked eye as a change of the color of the light propagating through the fiber, simplifying the setup needed for its use.