A5068265682- Advanced Fiber Optic Sensors
- Photonic and Optical Devices
- Photonic Crystal and Fiber Optics
- Semiconductor Lasers and Optical Devices
- Luminescence and Fluorescent Materials
- Organic Light-Emitting Diodes Research
- Spectroscopy Techniques in Biomedical and Chemical Research
- Nonlinear Optical Materials Studies
- Luminescence Properties of Advanced Materials
- Organic Electronics and Photovoltaics
- Protein Interaction Studies and Fluorescence Analysis
- Nanofabrication and Lithography Techniques
- Optical Imaging and Spectroscopy Techniques
- Solid State Laser Technologies
- Advanced Fiber Laser Technologies
- Spectroscopy and Chemometric Analyses
- Atomic and Subatomic Physics Research
- Glass properties and applications
- Optical Network Technologies
- Spectroscopy and Laser Applications
- Photorefractive and Nonlinear Optics
- Geochemistry and Geologic Mapping
- Photoreceptor and optogenetics research
- Mechanical and Optical Resonators
- Laser-Matter Interactions and Applications
The University of Adelaide
2014-2024
Australian Research Council
2022
ARC Centre for Nanoscale BioPhotonics
2018
University of St Andrews
2006-2013
University of Strathclyde
2013
National Centre of Scientific Research "Demokritos"
2007
National Technical University of Athens
2007
An organic semiconductor laser, simply fabricated by UV-nanoimprint lithography (UV-NIL), that is pumped with a pulsed InGaN LED demonstrated. Molecular weight optimization of the polymer gain medium on nanoimprinted distributed feedback resonator enables lowest reported UV-NIL laser threshold density 770 W cm−2, establishing potential for scalable fabrication compatible mass-produced LEDs.
A blue-emitting distributed feedback laser based on a star-shaped oligofluorene truxene molecule is presented. The gain, loss, refractive index, and (lack of) anisotropy are measured by amplified spontaneous emission variable-angle ellipsometry. waveguide losses very low for an organic semiconductor gain medium, particularly neat film. results suggest that truxenes promising reducing key parameter in the operation of lasers. Distributed lasers fabricated from solution spin-coating show...
In this work we demonstrate a suspended core microstructured optical fiber-based sensor platform for explosives detection based on the fluorescence quenching of surface-attached conjugated polymer poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene] (MEH-PPV). These fibers allow strong evanescent field interactions with surrounding media because their small size, and can sample minute liquid volumes. This is first demonstration fluorescent capable measuring samples loaded within an...
This work reports on the development of an optical fiber based probe for in vivo measurements brain temperature. By utilizing a thin layer rare-earth doped tellurite glass tip conventional silica robust probe, suitable long-term temperature can be fabricated. interrogated using portable measurement setup, allowing to performed outside standard laboratories.
We report the demonstration of a compact, all-solid-state polymer laser system comprising Gallium Nitride (GaN) semiconductor diode as pump source. The was configured surface emitting, distributed Bragg reflector (DBR), based on novel energy transfer blend Coumarin 102 and conjugated poly(2-methoxy-5-(2'-ethylhexyloxy)-1,4-phenylene vinylene). In this configuration, pumping possible both due to improved quality resonators harvesting light.
A study of the amplified spontaneous emission (ASE) properties three bisfluorene-cored dendrimers in solid state is reported. The results show that dendron type has a strong impact on photoluminescence quantum yield and affects ASE threshold, optical gain, loss coefficients. Optically pumped distributed feedback lasers operating blue spectral region were fabricated by spin coating dendrimer films top two-dimensional corrugated fused silica substrate. best lasing threshold 4.5μJ∕cm2 slope...
Abstract Optical pumping conditions for organic solid‐state lasers (OSLs) are discussed with particular emphasis on the use of gallium nitride based light‐emitting diodes (LEDs) as pump sources. LEDs operate in a regime where should be optimized short rise time and high peak intensity, whereas fall overall pulse duration less important. Lasers pumped this approach need to have very low thresholds which can now routinely created using (one‐dimensional) distributed feedback lasers. In case...
The probing of physiological processes in living organisms is a grand challenge that requires bespoke analytical tools. Optical fiber probes offer minimally invasive approach to report signals from specific locations inside the body. This perspective article discusses wide range such developed at Australian Research Council Centre Excellence for Nanoscale BioPhotonics. Our platforms use sensing modalities, including embedded nanodiamonds magnetometry, interferometric cavities refractive...
In this review, we examine recent developments in the field of chemical and biological sensing utilizing suspended‐core, exposed‐core, hollow‐core microstructured optical fibers. Depending on intended application, a host modalities have been utilized including labelled fluorescence techniques, label‐free methods such as surface plasmon resonance, fiber Bragg gratings, Raman scattering. The use various functionalization techniques adds specificity to both ions molecules. results shown here...
This paper explores the application and advantages of remote sensing, machine learning, mid-infrared spectroscopy (MIR) as a popular proximal sensing tool in estimation soil organic carbon (SOC). It underscores practical implications benefits integrated approach combining for SOC prediction across range applications, including comprehensive health mapping credit assessment. These advanced technologies offer promising pathway, reducing costs resource utilization while improving precision...
A tunable two-photon pumped solid-state laser based on polyfluorene is reported. detailed investigation of the absorption in for both nanosecond and femtosecond time regimes solution, allows determination most favorable conditions lasing. Tunable distributed feedback lasers are made by spin coating from a solution corrugated silica substrates lasing achieved under excitation at 640 nm with an absorbed energy density threshold 1.3 mJ/cm2. These results highlight alternative pumping scheme...
A novel approach for identifying explosive species is reported, using Raman spectroscopy in suspended core optical fibers. Numerical simulations are presented that predict the strength of observed signal as a function fiber geometry, with calculated trends verified experimentally and used to optimize sensors. This technique identify hydrogen peroxide water solutions at volumes less than 60 nL quantify microgram amounts material solvent’s signature an internal calibration standard. The same...
The two-photon absorption properties of bisfluorene dendrimers are investigated in both the nanosecond and femtosecond regime. By substituting different dendrons onto same chromophore (see figure), we examine effect on spectrum magnitude absorption. As these have high photoluminescence quantum yields, then proceed to make pumped dendrimer lasers.
Organic semiconductor lasers were fabricated by UV-nanoimprint lithography with thresholds as low 57 W/cm(2) under 4 ns pulsed operation. The nanoimprinted employed mixed-order distributed feedback resonators, second-order gratings surrounded first-order gratings, combined a light-emitting conjugated polymer. They pumped InGaN LEDs to produce green-emitting lasers, of 208 (102 nJ/pulse). These hybrid incorporate scalable process, compatible high-performance LEDs, therefore we have...
We demonstrate the generation of metastable krypton in long-lived $1{s}^{5}$ state using laser excitation. The atoms are excited through a two-photon absorption process into $2{p}^{6}$ pulsed optical parametric oscillator operating near 215 nm, after which decay quickly with branching ratio 75%. interaction dynamics modeled density matrix formalism and, by combining this experimental observations, we able to calculate photoionization and cross sections. When compared traditional approaches...
We report the fabrication of first extruded hollow core optical fiber with a single ring cladding holes, and its use in chemical sensing application. These suspended structures show antiresonance reflection waveguiding (ARROW) features visible part spectrum. The impact preform pressurization on geometry these fibers is determined by size different hole types preform. are used to perform Raman methanol, demonstrating their potential for future applications.
Microstructured optical fibers, particularly those with a suspended-core geometry, have frequently been argued as efficient evanescent-field fluorescence-based sensors. However, to date there has not systematic comparison between such fibers and the more common geometry of multi-mode fiber tip sensor. In this paper we make direct these two sensor geometries both theoretically experimentally. Our results confirm that provide significant advantage in terms total collected fluorescence signal...
A family of star-shaped conjugated oligofluorene molecules based around a central benzene core is studied with the aim identifying how changes in molecular structure can affect laser performance organic materials. As arm length increases optical transitions are found to move longer wavelength, there an increase photoluminescence quantum yield and corresponding reduction excitation density for amplified spontaneous emission. Distributed-feedback lasers on these materials tunable across...
We report here on the development of a method for inducing stroke in specific location within mouse brain through use an optical fiber.By capturing emitted fluorescence signal generated using same fiber it is possible to monitor photochemical changes real-time, and directly measure concentration strokeinducing dye, Rose Bengal, at infarct site.This technique reduces requirement post-operative histology determine if has successfully been induced animal, therefore opens up opportunity explore...
Abstract Understanding the upconversion pathways of a rare‐earth dopant is crucial to furthering use that material, either toward applications in imaging or elsewhere. This work outlines new analysis approach consists using two synchronized widely‐tunable laser sources explore properties upconverting materials. By examining sensitizer‐free nanoparticles based on matrix hexagonal sodium yttrium tetrafluoride (β‐NaYF 4 ) doped with praseodymium but no ytterbium sensitizer, “non‐degenerate”...