Open Access
Fiber optic sensor networks
(Elsevier, 2013) Pérez Herrera, Rosa Ana; López-Amo Sáinz, Manuel; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa
One of the main goals in fiber optic sensor technology is to multiplex together a high number of sensorsin the same network in order to share expensive terminal equipment and develop a system including multiple measuring points. Different kind of multiplexing networks for fiber optic sensors will be described and compared here, including networks using optical amplification and lasing multiplexing systems. State of the art in multiplexed and distributed sensor networks is also shown, focused on robust, remote and distributed Brillouin networks.
Open Access
Wavelength-switchable L-band fiber laser assisted by random reflectors
(EDP Open, 2023) Pérez Herrera, Rosa Ana; Roldán Varona, Pablo; Sánchez González, Arturo; Rodríguez Cobo, Luis; López Higuera, José Miguel; López-Amo Sáinz, Manuel; Ingeniería Eléctrica, Electrónica y de Comunicación; Institute of Smart Cities - ISC; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren
A wavelength-switchable L-band erbium-doped fiber laser (EDFL) assisted by an artificially controlled backscattering (ACB) fiber reflector is here presented. This random reflector was inscribed by femtosecond (fs) laser direct writing on the axial axis of a multimode fiber with 50 lm core and 125 lm cladding with a length of 17 mm. This microstructure was placed inside a surgical syringe to be positioned in the center of a high-precision rotation mount to accurately control its angle of rotation. Only by rotating this mount, three different output spectra were obtained: a single wavelength lasing centered at 1574.75 nm, a dual wavelength lasing centered at 1574.75 nm and 1575.75 nm, and a single wavelength lasing centered at 1575.5 nm. All of them showed an optical signal-to-noise ratio (OSNR) of around 60 dB when pumped at 300 mW
Open Access
Low noise dual-wavelength erbium fiber laser in single-longitudinal-mode operation
(Springer, 2012) Rota Rodrigo, Sergio; Pérez Herrera, Rosa Ana; Fernández Vallejo, Montserrat; López-Amo Sáinz, Manuel; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa
A new stable dual-wavelength fiber-ring laser based on erbium-doped fiber amplification is reported. The laser is based on ring resonators and employs fiber Bragg gratings to select the operation wavelengths. The topology of the laser has a significant influence in its performance: allowing an independent control of the losses for both lasing wavelengths and achieving a low noise configuration. As a result, it is experimentally demonstrated that both emission lines work in single-longitudinal-mode operation and the topology offers a better stability and higher optical signalto-noise ratios than similar configurations.
Open Access
Influence of saturable absorbers on fiber ring laser sensors
(SPIE, 2017) Rodríguez Cobo, Luis; Quintela, M. A.; Ruiz Lombera, Rubén; Pérez Herrera, Rosa Ana; López-Amo Sáinz, Manuel; López Higuera, José Miguel; Ingeniaritza Elektrikoa eta Elektronikoa; Institute of Smart Cities - ISC; Ingeniería Eléctrica y Electrónica
In this work, a fiber ring laser sensor has been employed to analyze the influence of passive Er-doped fiber acting as saturable absorber. Lasing modes of fiber ring lasers can be reduced by properly locating a saturable absorber that narrows the spectral width of the FBG that selects the lasing wavelength. Employing commercial Er-doped fiber, different configurations have been evaluated, reaching the SLM regime on a ring cavity of several meters. Thus, the achieved strain response of the whole sensor behaves at its mirror FBG, exhibiting linear response to strain.
Open Access
Láseres de fibra óptica basados en reflectores clásicos, estrechados y microperforados
(SEDOPTICA, 2021) Sánchez González, Arturo; Pérez Herrera, Rosa Ana; Roldán Varona, Pablo; Rodríguez Cobo, Luis; López Higuera, José Miguel; López-Amo Sáinz, Manuel; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren; Institute of Smart Cities - ISC; Ingeniería Eléctrica, Electrónica y de Comunicación; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa, PJUPNA1928
En este trabajo se presenta un estudio comparativo entre distintos láseres de fibra óptica altamente dopada con erbio, con cavidades lineales conformadas tanto por reflectores puntuales clásicos como reflectores distribuidos. El estudio analiza experimentalmente las principales prestaciones de cada configuración, destacando las mejoras en estabilidad de emisión y estrechamiento de línea alcanzadas con fibras estrechadas microperforadas.
Open Access
Single longitudinal mode lasers by using artificially controlled backscattering erbium doped fibers
(IEEE, 2021) Pérez Herrera, Rosa Ana; Roldán Varona, Pablo; Rodríguez Cobo, Luis; López Higuera, José Miguel; López-Amo Sáinz, Manuel; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren; Institute of Smart Cities - ISC; Ingeniería Eléctrica, Electrónica y de Comunicación; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa
In this work, we propose and experimentally demonstrate a new distributed short linear cavity fiber laser. At one of the cavity ends, fabricated by a commercial femtosecond fiber laser chirped pulse amplfier, an artificially controlled backscattering erbium doped fiber section has been connected. This distributed reflector acts also as a saturable absorber, leading to the generation of tunable and switchable single longitudinal-mode laser emissions. The distributed reflector consists of 9 micro-drilled sections of about 1cm each one and randomly spread throughout 2 meters of highly doped erbium fiber. The total length of the fiber laser is 9.5 m and the laser shows a single mode behavior at all the emitted wavelengths. Using this new kind of reflecting saturable absorber, single and multiple single-mode emissions can be obtained. The achieved laser presents a pump threshold as low as 45 mW and shows up to 8 different single-mode emission lines with an optical signal to noise ratio of 45dB.