Abstract

An experimental investigation of transition modes of long-period gratings (LPG) is reported. Coating LPGs with a material of high refractive index causes a reorganization of the cladding modes, leading to a substantial increase in sensitivity to changes in the surrounding refractive index (SRI). The sensitivity of a coated LPG to SRI over a given range of SRI is a function of coating thickness. In this study, the thickness of polystyrene coatings applied by dip coating was measured by scanning electron microscopy. The LPG sensors were used to monitor dissolution of liquid CO₂ in deionized water at high pressure, simulating use of the sensors to monitor geologically sequestered CO₂ in a deep aquifer.

© 2014 IEEE

Mode transition in high refractive index coated long period gratings

A. Cusano, A. Iadicicco, P. Pilla, L. Contessa, S. Campopiano, A. Cutolo, and M. Giordano
Opt. Express 14(1) 19-34 (2006)

Transition mode long period grating biosensor with functional multilayer coatings

Pierluigi Pilla, Viera Malachovská, Anna Borriello, Antonietta Buosciolo, Michele Giordano, Luigi Ambrosio, Antonello Cutolo, and Andrea Cusano
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Cladding mode reorganization in high-refractive-index-coated long-period gratings: effects on the refractive-index sensitivity

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Opt. Lett. 30(19) 2536-2538 (2005)

Long period gratings coated with hafnium oxide by plasma-enhanced atomic layer deposition for refractive index measurements

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P. Pilla, P. Foglia Manzillo, V. Malachovska, A. Buosciolo, S. Campopiano, A. Cutolo, L. Ambrosio, M. Giordano, and A. Cusano
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