University of Crete
Department of Materials Science and Technology
Ελληνικά
English
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PhD Candidate

NIKOLAOS KORAKAS

Email

nkorakas@materials.uoc.gr

Phone

Office

Personal web page

Title

Supervisor

KAFESAKI MARIA, Associate Professor, Materials Science & Technology Dept. - UOC

Committee Members

PETEKIDIS GEORGIOS, Professor, Materials Science & Technology Dept. - UOC

PISSADAKIS STAVROS, Researcher B, FORTH, Heraklion Crete GREECE

Abstract

Fiber Bragg gratings (FBGs) several years since their first demonstration by Hill et al. constitute backbone optical components for a vast number of telecom, laser development and sensing applications. Recently, except for the FBGs which are now routinely fabricated in standard optical fiber, Bragg gratings and structural long-period gratings have also been inscribed in microstructured optical fibers (MOFs) and photonic crystal fibers (PCFs). The periodic modulation in the refractive index of solid fiber core and relief Bragg gratings are the two types of FBG’s with different fabrication methods and with distinct capabilities as well. The expansion of the interrogation capabilities is the main advantage of relief FBGs compared with reflectors fabricated in standard optical fibers, where the infiltration of gases or liquids are not intrinsic. Relief FBG’s as well as standard FBG’s reflects a specific wavelength of light that changes based on the surrounding conditions as the evanescence field propagating along the fiber axis. For the previous reasons Bragg reflectors inscribed in MOFs and PCFs are necessary photonic elements towards the elaboration of the “lab-in-a-fiber” protocol. The purpose of my thesis is the use of aforementioned inscribed relief Bragg gratings in hollow core photonic crystal fiber in order to manufacture a highly sensitive, compact and relatively low cost, greenhouse gases trace sensor based on photothermal effect in a hollow-core fiber Fabry–Perot interferometer.