• Analysis of one-dimensional photonic band gap structures with a liquid crystal defect towards development of fiber-optic tunable wavelength filters 

      Del Villar, Ignacio Upna; Matías Maestro, Ignacio Upna; Arregui San Martín, Francisco Javier Upna; Claus, Richard O. (Optical Society of America, 2003)   Artículo / Artikulua  OpenAccess
      A theoretical analysis of a fiber optical photonic band gap based tunable wavelength filter is presented. The design presented here is based on the quarter wave reflector with a liquid crystal defect layer in the middle ...
    • Arc-induced long period fiber gratings in the dispersion turning points 

      Colaço, Celso; Caldas, Paulo; Del Villar, Ignacio Upna; Chibante, Rui; Rego, Gaspar (IEEEOptical Society of America, 2016)   Artículo / Artikulua  OpenAccess
      We demonstrated the possibility to inscribe longperiod fiber gratings (LPFGs) in a B/Ge codoped fiber by using grating periods shorter than 150 μm. We also have arc-induced in the SMF 28 fiber an LPFG in the dispersion ...
    • Deposition of an overlay with electrostactic self-assembly method in long period fiber gratings 

      Del Villar, Ignacio Upna; Achaerandio, Miguel Upna; Matías Maestro, Ignacio Upna; Arregui San Martín, Francisco Javier Upna (Optical Society of America, 2005)   Artículo / Artikulua  OpenAccess
      It was proved that the deposition of an overlay material onto a long-period fiber grating causes important shifts in the wavelengths of the typical attenuation bands that are caused by coupling between cladding and core ...
    • Deposition of coatings on long-period fiber gratings: tunnel effect analogy 

      Del Villar, Ignacio Upna; Matías Maestro, Ignacio Upna; Arregui San Martín, Francisco Javier Upna (Springer, 2006)   Artículo / Artikulua  OpenAccess
      The sensitivity of Long-period fiber gratings (LPFGs), coated with high-refractive-index thin film overlays, to the refractive index and the thickness of the overlay, and to the ambient refractive index, can be enhanced ...
    • Design rules for lossy mode resonance based sensors 

      Del Villar, Ignacio Upna; Hernáez Sáenz de Zaitigui, Miguel Upna; Ruiz Zamarreño, Carlos Upna; Sánchez Zábal, Pedro Upna; Fernández Valdivielso, Carlos Upna; Arregui San Martín, Francisco Javier Upna; Matías Maestro, Ignacio Upna (Optical Society of America, 2012)   Artículo / Artikulua  OpenAccess
      Lossy mode resonances can be obtained in the transmission spectrum of cladding removed multimode optical fiber coated with a thin-film. The sensitivity of these devices to changes in the properties of the coating or the ...
    • Development of an optical refractometer by analysis of one-dimensional photonic bandgap structures with defects 

      Matías Maestro, Ignacio Upna; Del Villar, Ignacio Upna; Arregui San Martín, Francisco Javier Upna (Optical Society of America, 2003)   Artículo / Artikulua  OpenAccess
      A theoretical analysis of an optical fiber photonic-bandgap-based refractometer is presented. The design is based on a quarter-wave ref lector with one defect. By modifying both the real and the imaginary parts of the index ...
    • Enhancement of sensitivity in long period fiber gratings with deposition of low refractive index materials 

      Del Villar, Ignacio Upna; Matías Maestro, Ignacio Upna; Arregui San Martín, Francisco Javier Upna (Optical Society of America, 2005)   Artículo / Artikulua  OpenAccess
      It was proved [Opt. Lett. 30, 720 (2005)] that the deposition of an overlay of higher refractive index than that of the cladding on a long-period fiber grating (LPFG) causes large shifts in the attenuation bands induced by ...
    • ESA-based in-fiber nanocavity for hydrogen–peroxide detection 

      Del Villar, Ignacio Upna; Matías Maestro, Ignacio Upna; Arregui San Martín, Francisco Javier Upna; Claus, Richard O. (IEEE, 2005)   Artículo / Artikulua  OpenAccess
      A fiber-optic sensor sensitive to hydrogen peroxide has been designed based on the electrostatic layer-by-layer selfassembly method. Prussian blue has been deposited in a polymeric structure formed by Poly(allylamine ...
    • Etched and nanocoated SMS fiber sensor for detection of salinity concentration 

      Cardona-Maya, Yamile; Del Villar, Ignacio Upna; Socorro Leránoz, Abián Bentor Upna; Corres Sanz, Jesús María Upna; Arregui San Martín, Francisco Javier Upna; Botero-Cadavid, Juan F. (MDPI, 2017)   Contribución a congreso / Biltzarrerako ekarpena  OpenAccess
      An optical fibre refractometer has been developed by etching and deposition of a thin film of indium tin oxide (ITO) on a single-mode-multimode-single-mode (SMS) fibre structure. The interference between modes in this ...
    • Etched LPFGs in reflective configuration for sensitivity and attenuation band depth increase 

      Del Villar, Ignacio Upna; Socorro Leránoz, Abián Bentor Upna; Corres Sanz, Jesús María Upna; Matías Maestro, Ignacio Upna; Cruz, José Luis; Rego, Gaspar (IEEE, 2016)   Artículo / Artikulua  OpenAccess
      A reflection configuration setup for long-period fiber gratings is presented. It permits to obtain a unique band with attenuation double than that obtained in transmission configuration, which is interesting for ...
    • Experimental demonstration of lossy mode and surface plasmon resonance generation with Kretschmann configuration 

      Del Villar, Ignacio Upna; Torres Landívar, Víctor Upna; Beruete Díaz, Miguel Upna (Optical Society of America, 2015)   Artículo / Artikulua  OpenAccess
      Lossy mode resonances (LMRs) and surface plasmon resonaces (SPRs) are obtained experimentally with a Kretschmann configuration using a BK7 glass prism with all sides polished and coated with indium tin oxide (ITO). The ...
    • Fabrication of Bragg gratings on the end facet of standard optical fibers by sputtering the same material 

      Ascorbe Muruzabal, Joaquín Upna; Corres Sanz, Jesús María Upna; del Villar, Ignacio Upna; Arregui San Martín, Francisco Javier Upna; Matías Maestro, Ignacio Upna (IEEE, 2016)   Artículo / Artikulua  OpenAccess
      A sputtering process has been applied to deposit quarter-wavelength stacks on the end facet of cleaved optical fibers by using only one sputtering target. Standard multimode optical fibers were used as substrates to fabricate ...
    • Fiber optic multiple-wavelength filter based on one dimensional photonic bandgap structures with defects 

      Del Villar, Ignacio Upna; Matías Maestro, Ignacio Upna; Arregui San Martín, Francisco Javier Upna (IEEE, 2004)   Artículo / Artikulua  OpenAccess
      In this paper, a theoretical analysis is given of an optical fiber multiple-wavelength tunable filter based on a onedimensional (1-D) photonic bandgap (PBG) structure with four defects. To understand the positioning of ...
    • Fiber-optic lossy mode resonance sensors 

      Arregui San Martín, Francisco Javier Upna; Del Villar, Ignacio Upna; Corres Sanz, Jesús María Upna; Goicoechea Fernández, Javier Upna; Ruiz Zamarreño, Carlos Upna; Elosúa Aguado, César Upna; Hernáez Sáenz de Zaitigui, Miguel Upna; Rivero Fuente, Pedro José Upna; Socorro Leránoz, Abián Bentor Upna; Urrutia Azcona, Aitor Upna; Sánchez Zábal, Pedro Upna; Zubiate Orzanco, Pablo Upna; López Torres, Diego Upna; Acha Morrás, Nerea de Upna; Matías Maestro, Ignacio Upna (Elsevier, 2014)   Contribución a Congreso / Biltzarrerako ekarpena  OpenAccess
      In the last 4 years, experimental evidences about the potential use of optical sensors based on Lossy Mode Resonances (LMR) have been presented in the literature. These LMR sensors have some similarities with Surface ...
    • Fiber-optic nanorefractometer based on one-dimensional photonic-bandgap structures with two defects 

      Del Villar, Ignacio Upna; Matías Maestro, Ignacio Upna; Arregui San Martín, Francisco Javier Upna (IEEE, 2004)   Artículo / Artikulua  OpenAccess
      A theoretical analysis of a fiber-optic photonic- bandgap (PBG)-based nanorefractometer is presented. Changes up to 11.2 dB in the optical output power in an index of refraction range of 1.7 with a sensitivity of 1.5 ...
    • Fringe generation with non-uniformly coated long-period fiber gratings 

      Del Villar, Ignacio Upna; Arregui San Martín, Francisco Javier Upna; Matías Maestro, Ignacio Upna; Cusano, Andrea; Paladino, Domenico; Cutolo, Antonello (Optical Society of America, 2007)   Artículo / Artikulua  OpenAccess
      In this work, the spectral characteristics of non-uniform symmetrically ring shaped coatings deposited on long-period fiber gratings (LPFGs) have been theoretically and experimentally investigated. To optimize the ...
    • Generation of lossy mode resonances by deposition of high-refractive-index coatings on uncladded multimode optical fibers 

      Del Villar, Ignacio Upna; Ruiz Zamarreño, Carlos Upna; Sánchez Zábal, Pedro Upna; Hernáez Sáenz de Zaitigui, Miguel Upna; Fernández Valdivielso, Carlos Upna; Arregui San Martín, Francisco Javier Upna; Matías Maestro, Ignacio Upna (IOP Publishing Ltd, 2010)   Artículo / Artikulua  OpenAccess
      A comparative study of lossy mode resonances generated by depositing two different materials is presented. The two materials selected are indium tin oxide (ITO) and indium oxide. The two materials present different ...
    • Generation of lossy mode resonances with absorbing thin-films 

      Del Villar, Ignacio Upna; Ruiz Zamarreño, Carlos Upna; Hernáez Sáenz de Zaitigui, Miguel Upna; Arregui San Martín, Francisco Javier Upna; Matías Maestro, Ignacio Upna (IEEE, 2010)   Artículo / Artikulua  OpenAccess
      The generation of lossy mode resonances with absorbing thin-films is analyzed with electromagnetic theory. The main differences with surface plasmon resonances are presented and some rules are given towards an optimum ...
    • Generation of selective fringes with cascaded long-period gratings 

      Del Villar, Ignacio Upna; Achaerandio, Miguel Upna; Arregui San Martín, Francisco Javier Upna; Matías Maestro, Ignacio Upna (IEEE, 2006)   Artículo / Artikulua  OpenAccess
      The inscription of cascaded long-period gratings of different periods in optical fiber permits us to obtain both narrowband and wideband filters in the same spectrum. If used as an optical transducer, it may permit us ...
    • Generation of surface plasmon resonance and lossy mode resonance by thermal treatment of ITO thin-films 

      Del Villar, Ignacio Upna; Ruiz Zamarreño, Carlos Upna; Hernáez Sáenz de Zaitigui, Miguel Upna; Sanchez, Pedro; Arregui San Martín, Francisco Javier Upna; Matías Maestro, Ignacio Upna (Elsevier, 2014)   Artículo / Artikulua  OpenAccess
      Silicon wafers coated with IndiumTinOxide (ITO) by application of sputtering technique have been characterized after different post-annealing techniques, showing that this last factor is critical for the quality of the ...