Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 20 of 47 for “"Evanescent Field"”.
-
Optimising the plastic optical fibre evanescent field biofilm sensor
… plastic optical fibre (POF) sensors using evanescent field modulation. The exposed polymethylmethacrylate (PMMA) core of the POF fibre forms the sensor interface that detects refractive index changes of a measurand acting as the cladding. When a liquid measurand is used, the sensor can …
-
Evanescent field enhanced fluorescence on a photonic crystal surface
… wavelengths at which strong electromagnetic fields are utilized to enhance the intensity of surface-bound fluorophore excitation. Meanwhile, the leaky resonant modes of PCs can be used to direct emitted photons within a narrow range of angles for more efficient collection by a fluorescence …
-
Thin film integrated optical waveguides for biosensing using local evanescent field detection
… the core of the waveguide is a decaying evanescent light field that extends into the cladding layers. The intensity profile of the evanescent field is dependent on the refractive index of the cladding. The changes in the local intensity of the evanescent field can be used to detect …
-
Evaluation of a planar optic waveguide as a platform for evanescent field chemical sensor development
… interfacial sensitivity of the device for evanescent field chemical sensor development in the visible spectral region. However, it was discovered that selective prism and grating coupling to discrete waveguide modes was not possible due to strong crosstalk between modes in multiple mode …
-
Development and Optimisation of an Optofluidic Evanescent Field Nano Tweezer System for Trapping Nanometre Crystals for Synchrotron X-Ray Diffraction Experiments
… opening the technique to other research fields, e.g. biomedical, archaeological or engineering. This work focusses on a specific sub-section of the loading challenge, introducing a method which could achieve reliable sample loading of crystals below 5 µm, thus opening up the low micro and …
-
Propulsion of polymer particles on caesium ion-exchanged channel waveguides for stem cell sorting applications
… The manipulation of particles in the evanescent field of a channel waveguide potentially allows for sorting and trapping of several particles and cells simultaneously. In the evanescent field above an optical channel waveguide, particles experience three optical forces; i) a transverse …
-
Resonant Detection of Nano to Microscopic Objects Using Whispering Gallery Modes
… sensor. Although the resonance is stealth, an evanescent field extends from the microsphere surface the distance of a wavelength into the surrounding medium. This thesis demonstrates how label-free molecules binding to the microsphere surface perturb the optical resonance by interaction with …
-
Optical micro- and nanofibres: Higher mode generation and particle manipulation studies
This thesis is centred on two experimental fields of optical micro- and nanofibre research; higher mode generation/excitation and evanescent field optical manipulation. Standard, commercial, single-mode silica fibre is used throughout most of the experiments; this generally produces high-quality, …
-
Integrated optical switching using titanium nitride micro electromechanical systems
… conductive material into the electromagnetic evanescent field of the ring waveguide results in loss in the propagating light within, disabling the resonance and the filtering capabilities of the ring resonator. Therefore, by actuating the MEMS bridge in and out of the waveguide's evanescent …
-
Swift Electro-Optic Modulator
… a nonlinear optical polymer, NLOP, film into the evanescent field of a D-fiber. In this way electric fields applied to the NLOP can be used to influence the light propagating through the fiber. The two initial processes in fabricating the modulator are accessing the evanescent field of the D-fiber …
-
In-line optical fiber holography
… highly efficient holographic storage medium. The evanescent field of the fiber is used as the reference beam to form an interference pattern with an object wave. The interference of the two fields is recorded in the DCG and forms the hologram. The holograms recorded have a grating type structure …
-
Particle-modified Surface Plasmon Resonance Biosensor
… the implications of a particle-modified evanescent field on the signal amplitude and kinetics, for an exemplar affinity binding between immobilised IgG and its anti-IgG complement. Submicron silica particles were synthesized as carriers for the bio-recognition elements. They were then …
-
A fiber optic polarimeter for use in chemical analysis
… FIA detector. Its more intriguing future lies in evanescent field sensor applications and studies of chiroptical surface interactions.
-
Investigations on the development of a novel hybrid sensor for environmental monitoring applications.
… envisaged integrating optical and electrical fields in addition to nanomaterials. This thesis reports investigations on enhancing the sensitivity/selectivity through optical, nanomaterials and electrochemical routes, and then integrating these to realise a hybrid sensor. A novel optical sensor …
-
Experiments Towards the Realization of a Nanofiber Guided Dipole Trap
… optical nanofiber (TNF) that enables optical fields to interface with trapped neutral atoms in their vicinity. In such a configuration, the guided light exhibits a large portion of evanescent field into the vacuum thus laser cooled atoms can couple to the fiber mode. By trapping and cooling …
-
In-line Fiber Polarizer
… lateral surface of the cladding to within the evanescent field present around the fiber core. Several thin films including a metal film are applied to the polished section of the fiber. Ionic self-assembled monolayer method was used to coat the polished fiber with thin film.
-
Analysis of Side-Polished Few-Mode Optical Fiber
Side-polished fiber allows access to the evanescent field propagating in the cladding of a few-mode fiber. This cladding mode is analyzed and experimentally validated to further the design of a novel class of fiber optic devices. To do this, specific modes are excited in the polished fiber using a …
-
A chemical sensor based on surface plasmon resonance on surface modified optical fibers
… the lateral surface of an optical fiber to its evanescent field surrounding the fiber core. One or more thin films are applied to the polished section of the fiber to produce the sensing element. One of the films is the metal silver, which acts as the support for the surface plasmon. Under the …
-
Silicon based photonic crystal coupled to an optical cavity for highly sensitive biodetection
… further increase fluorescent output via stronger evanescent field. A fluorescent dye tagged protein detection experiment was conducted on the new PC showing that it provides 10x SNR, opening the door for detection of biomarkers in sub-pg/ml range.
Page 1 of 3