Theses and Dissertations
Issuing Body
Mississippi State University
Advisor
Wang, Chuji
Committee Member
Arnoldus, Henk F.
Committee Member
Monts, David L.
Date of Degree
12-10-2010
Document Type
Graduate Thesis - Open Access
Major
Physics
Degree Name
Master of Science (M.S.)
College
College of Arts and Sciences
Department
Department of Physics and Astronomy
Abstract
We combine the evanescent field (EF) sensing mechanism with the fiber loop ringdown (FLRD) sensing scheme to create FLRD-EF sensors. The EF sensor heads are fabricated by etching the cladding of a single-mode fiber (SMF), while monitoring the etching process by the FLRD technique in real-time, on-line with high control precision. The effect of the sensor head dimensions on the sensors' detection sensitivity and response time are investigated. The EF scattering (EFS) sensing mechanism is combined with the FLRD detection scheme to create a new type of fiber optic index sensor. The detection limit for an optical index change is 3.2×10-5. This is the highest sensitivity for a fiber optic index sensor so far, without using any chemical-coating or optical components at the sensor head. A new type of index-based biosensor using high sensitivity FLRDEFS technique to sense deoxyribonucleic acid (DNA) and bacteria (Escherichia coli) is created.
URI
https://hdl.handle.net/11668/19199
Recommended Citation
Herath, Chamini Saumya, "Fiber Loop Ringdown Evanescent Field Sensors" (2010). Theses and Dissertations. 2267.
https://scholarsjunction.msstate.edu/td/2267