Surface plasmon waves , fiber optic

Modified fiber-optic-based sensors can be used for sensing pollutants, explosives, drugs, pharmaceuticals, and miscellaneous organics (Yeh et al. 2006). Optical fibers coated with porous silica can be used to detect the presence of chlorinated hydrocarbons. Alternatively, these compounds can also be detected using fiber-optic-coupled surface plasmon resonance methods. Aromatic compounds were detected by evanescent wave absorption spectroscopy. Suitably modified fiber-optic array tips can be used to detect presence of explosive materials (Wolfbeis 2000). 

DeMarco DV, Lim DV (2001) Direct detection of escherichia coliol57 h7 in unpasterized apple juice with an evanescent wave sensor. J Rapid Meth Automation Micro 9 241-257 Diez A, Andres MV, Cruz JL (2001) In-line fiber-optic sensors based on the excitation of surface plasma modes in metal-coated tapered fibers. Sensors Actuators B Chem 73 95-99 Dostalek J, Ctyroky J, Homola J, Brynda E, Skalsky M, Nekvindova P, Spirkova J, Skvor J, Schrofel J (2001) Surface plasmon resonance biosensor based on integrated optical waveguide. Sensors Actuators B Chem 76 8-12... 

Benson DK, Tracy CE, Lee S-H, Hishmeh GA, Haberman DP, Ciszek PA (1998) Low-cost, fiber-optic hydrogen gas detector using guided-wave, surface-plasmon resonance in chemochromic thin films. NREL/CP-590-25611, pp 1-18... 

Jakubik WP, Urbanczyk MW, Kochowski S, Bodzenta J (2003) Palladium and phthalocyanine bilayer films for hydrogen detection in a surface acoustic wave sensor system. Sens Actuators B 96 321-328 Jung CC, Saaski EW, McCrae DA (1998) Fiber optic hydrogen sensor. In Jung CC, Udd E (eds) Proceedings of the SPIE, Fourth Pacific Northwest Fiber Optic Sensor Workshop, vol 3489, pp 9-15 Kashyap R, Nemova G (2009) Surface plasmon resonance-based fiber and planar waveguide sensors. J Sensors 2009 645162... 

Note that the intensity of the evanescent wave in an atom mirror can be increased by two or three orders of magnitude on account of excitation of surface plasmons produced by introducing a thin metal layer into the dielectric-vacuum interface (Esslinger et al. 1993). Another method to intensify the evanescent wave is to introduce a dielectric film of high refractive index, which produces a dielectric optical fiber for the laser radiation. The repeated reflection of the laser light from the dielectric-vacuum and dielectric-dielectric interfaces substantially increases the intensity of the evanescent wave (Kaiser et al. 1994). 

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