A5068136695- Advanced Fiber Optic Sensors
- Photonic and Optical Devices
- Advanced Fiber Laser Technologies
- Photonic Crystals and Applications
- Analytical Chemistry and Sensors
- Plasmonic and Surface Plasmon Research
- Advanced MEMS and NEMS Technologies
- Mechanical and Optical Resonators
- Semiconductor Lasers and Optical Devices
- Photonic Crystal and Fiber Optics
- Near-Field Optical Microscopy
- Orbital Angular Momentum in Optics
- Advanced ceramic materials synthesis
- Optical Coatings and Gratings
- Water Systems and Optimization
- Advanced Antenna and Metasurface Technologies
- Advanced materials and composites
- Antenna Design and Analysis
- Non-Invasive Vital Sign Monitoring
- Nanofabrication and Lithography Techniques
- MXene and MAX Phase Materials
- Gas Sensing Nanomaterials and Sensors
- Intermetallics and Advanced Alloy Properties
- Optical Wireless Communication Technologies
- Structural Health Monitoring Techniques
City, University of London
2022-2023
University College London
2023
Southern University of Science and Technology
2019-2021
Central Glass and Ceramic Research Institute
1999-2018
Council of Scientific and Industrial Research
2011-2018
MaXentric Technologies (United States)
2018
Bangladesh Council of Scientific and Industrial Research
2017
Academy of Scientific and Innovative Research
2016-2017
The University of Sydney
2009
Purdue University West Lafayette
1984
Long period grating (LPG) at turn-around-point (TAP) has been studied with a view to enumerate the dependence of sensitivity particular resonant mode TAP surrounding refractive index on initial coupling strength. It shown theoretically and also validated experimentally that can be enhanced significantly by tailoring strength cladding wavelength near TAP. Sensitivity characteristics have for in range 1.335-1.360, which is interest field biosensors, where conventional LPGs relatively small. We...
In this paper, a detailed investigation on the modeling of long-period fiber grating (LPFG) sensors is discussed with aim providing more realistic solution for their use in biosensing. Add-layer sensitivity, i.e., sensitivity sensor to an additional layer adhered onto surface, quantified and clear complete analysis about influence average thickness deposited biological sensing layers, as well change refractive index these resonant wavelength cladding modes LPFG provided. close mode...
A new temperature fiber ring laser (FRL) sensor based on a cascaded Sagnac loops structure is proposed and experimentally demonstrated. The optical FRL consists of by inserting two polarization-maintaining fibers (PMF) with slightly different lengths. PMF length 56 cm 75 are used in as filter sensing unit cavity. working principle the phase shift (θ) caused birefringence between principal polarization modes enhance sensitivity constructing Vernier-scale. In an appropriate range (25 °C - 31...
In this work, a 45° tilted fiber grating (TFG) is used as waveguide coupler for the development of portable interrogation system to access remotely placed optical sensors. The TFG directly connected remote sensor and serves highly efficient light between unit sensor. Variation strain temperatures are measured with standard Bragg (FBG) sensor, which A beam from coupled into by lenses, mirrors collimator acted input FBG. Reflected FBG back via same TFG. being receiver transmitter constituent...
A highly sensitive optical fiber sensor for the measurement of axial force and refractive index (RI) is presented. The consists a distributed Bragg reflector (DBR) based laser, laser cavity DBR polished to D-shape by wheel polishing system. Birefringence has been introduced with side fiber, then, it utilized sensing applications. working principle device on change in beat frequency two orthogonal polarization modes external perturbations. In this work, shown that dual can be used RI-based...
Recently, two special photonic jets, hooks and twin have been proposed to deal with complex conditions in nanoscale manipulation. Photonic are generated by a single light plane wave an asymmetric microparticle, while the jets produced incident beams. In this letter, we presented demonstrated method combine jets. A symmetric twin-ellipse microcylinder, used research. The curvature degree, length maximum E <sup xmlns:mml="http://www.w3.org/1998/Math/MathML"...
The performance of free-space optical data transmission is severely deteriorated by the fluctuation signal intensity, which resulted from bias drift electro-optical modulation devices. In order to improve communication systems, a bias-drift avoiding, beam steered wireless system presented based on polarization for first time best our knowledge. An in-fiber diffraction device 45° tilted fiber grating (TFG) serves simultaneously as an polarizer, light emitter, and steerer in proposed system,...
We present our theoretical study on the design of long period fiber grating (LPFG) sensor where its add-layer sensitivity is enhanced. Add-layer quantifies to changes taking place within few tens nanometers around receptor molecules. Two different methodologies: use dual overlay layer and tailoring intermodal separation between two cladding modes have been used enhance sensisstivity. Using coupled mode analysis, we compute several examples carry out a detailed comparative analysis results...
We present a detailed numerical analysis that describes the influence of palladium (Pd) layer thickness on spectral characteristics long-period fiber gratings (LPFGs) and their response to uptake hydrogen. The investigation is carried out with view determining an optimal design high-sensitivity LPFG-based hydrogen sensors. Coupled differential equations for four-layer waveguide structure have been solved using matrix method considering Pd finite cladding. Response higher order cladding modes...
We report a high sensitive refractive index (RI) sensor using fiber Bragg grating (FBG) where azimuthally symmetric resonant cladding modes were used for RI sensing. enhanced the sensitivity by tailoring effective of mode to an optimum value so that has maximum around specific surrounding RI. tailored clad controlled deposition thin polymer layer having higher than cladding. Experiments show (LP0,12) standard FBG with overlay coating medium 1.333 is ~ 2600 pm/RIU. The proposed sensing...
Bio-chemical sensors are expected to offer high sensitivity and specificity towards the detection of an analyte. It has been found that optical based on long period fiber gratings (LPFGs) meet most these requirements, particularly when coated with thin high-refractive index overlays proper bio-functionalization. In this paper, influence properties overlay material LPFG bio-analytes is analyzed. observed a particular cladding mode can be changed drastically adhesion few tens 'nm' bio-layers...
Real-time monitoring of the state charge (SOC) batteries used in a wide variety applications is becoming increasingly important, especially given impetus by current targets towards “net-zero”. In this research, an advanced approach was involving fiber Bragg grating (FBG)-based sensors that were developed and implemented for measurement key parameters required to ensure optimum battery performance. work, one biggest challenges assess (and then map) data from sensor system tackled order better...
A method of fabrication a reflection-type long-period fiber grating (LPFG) operating near turn around point has been presented along with theoretical details. We have shown that removal multiple resonant bands due to unwanted phase shift introduced after cleaving the at an arbitrary location can be accomplished by tailoring matching curve cladding mode. This also allows us enhance sensitivity sensor. The cleaved any within structure. Therefore, probe-type sensor head made considerably small....
Strong regenerated gratings are reported, with a maximum grating strength exceeding (40-50) dB. Further annealing between 1000 and 1100°C leads to stabilised ~18dB in strength. This suffers no further degradation at for the period monitored, over 4 hrs.
The role of rotational alignment during grating writing is comprehensively examined by the measurement core luminescence from a Ge-doped 12 ring photonic crystal fibre, computer simulation transmission and, definitively, inscription gratings at three angles-0°, 30° and optimum luminescent angle for this 21.5°.All experimental results were in accordance with each other agreement simulation.Control fibre demonstrably critical reproducible writing.
A novel mechanism of sensitivity enhancement D-shaped fiber-based surface plasmon resonance (SPR) sensors for the optofluidic device has been proposed. The sandwiched structure platform is developed with metal-coated fiber as sensing device, while another thin metal layer situated under inner wall substrate a second to construct microchannel. It found that D-type SPR sensor enhanced significantly In proposed structure, measurand analyte considered sandwich channel between two layers....
In this work, a detailed study on volume and surface refractive index (RI) sensitivity of cladding modes for fiber Bragg grating (FBG) based sensor is presented. Surface RI the mode FBGs has been illustrated quantified with concept add-layer first time to best our knowledge. A investigation transition higher-order revisited important characteristics are observed which could open new designing path fabrication innovative way use family optical grating-based sensors. The effect "mode...