Browsing Department of Chemistry Faculty Publications by Publish Date
Now showing items 1-20 of 78
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Assessment of the Oxidative Stability of Lubricant Oil using Fiber-Coupled Fluorescence Excitation–Emission Matrix Spectroscopy
(2016-02-24)The fluorescence of antioxidant additives in lubricant oil was used as an indicator of oxidative stability of the oil. It was found that the decrease in fluorescence intensities of phenyl--napthylamine, its dimer, and ... -
Absolute Absorption Cross-Section Measurement of a Submonolayer film on a silica microresonator
(2016-02-24)Conventional absorption spectroscopy is not nearly sensitive enough for quantitative overtone measurements on submonolayer coatings. While cavity-enhanced absorption detection methods using microresonators have the potential ... -
Quantification of Different Water Species in Acetone using a NIR-Triple-Wavelength Fiber Laser
(2016-02-25)A fiber laser using a thulium-doped ZBLAN gain medium was used to generate laser radiation simultaneously at 1461, 1505 and 1874 nm, with > 5 mW output power at each of the wavelengths. The laser was used to quantify the ... -
Three-Wavelength Tm3+:ZBLAN Fiber Laser and its Applications in Water Detection
(2016-02-25)We demonstrate a three-wavelength Tm3+:ZBLAN fiber laser emitting simultaneously at 1460 nm, 1503 nm, and 1873 nm and its application in single-pass absorption measurements for detecting and quantifying water concentration ... -
Enhanced Nanoparticle Detection with Liquid Droplet Resonators
(2016-02-25)Whispering gallery mode particle sensing experiments are commonly performed with solid resonators, whereby the sensing volume is limited to the weak evanescent tail of the mode near the resonator surface. In this work we ... -
Cavity-Enhanced Photoacoustic Detection Using Acoustic and Fiber-Optic Resonators
(2016-03-02)A wineglass has been used as an acoustic resonator to enhance the photoacoustic signal generated by laser excitation of absorbing dyes in solution. The amplitude of the acoustic signal was recorded using a fiber-optic ... -
Spatial Coating Inhomogeneity of Highly Reflective Mirrors Determined by Cavity Ringdown Measurements
(2016-03-02)The inhomogeneity of high-reflectivity mirror coatings is a potential error source in the application of the cavity ringdown technique. Here, the ringdown times for different transverse modes were recorded. Together with ... -
Direct Sensing in Liquids Using Whispering-Gallery-Mode Droplet Resonators
(2016-03-03)Liquid droplets suspended by the tip of a thin wire, a glass capillary, or a needle form high-Q optical resonators, thanks to surface tension. Under gravity equilibrium conditions, the maximum drop diameter is approximately ... -
Gas Sensing Using Polymer-Functionalized Deformable Fabry–Perot Interferometers
(2016-03-03)We report a chemical vapor sensor in which polymer swelling, upon analyte absorption, is used to deform an on-chip silicon Fabry–Perot interferometer (FPI). The magnitude of the deformation, recorded through the resonance ... -
Phase-Shift Cavity Ring-Down Spectroscopy on a Microsphere Resonator by Rayleigh Backscattering
(2016-03-04)The optical ring-down time in a silica microsphere resonator is measured using phase-shift cavity ring-down spectroscopy. When detecting Rayleigh backscattered light that is coupled into the input waveguide it is found ... -
Monitoring of Vapor Uptake by Refractive Index and Thickness Measurements in Thin Films
(2016-03-04)We report a method for real-time monitoring of vapor uptake by simultaneous detection of the refractive index, 𝑛 , and thickness, 𝑑 , of thin transparent films with a precision of 𝛿𝑛=10 −4 and 𝛿𝑑<100 nm . The setup ... -
Near Infrared Absorption Detection in Picolitre Liquid Volumes Using Fiber Loop Ring-Down Detection
(2016-03-07)Cavity ring-down spectroscopy is performed using a single-mode fibre loop as an optical cavity. The loop contains absorption cells for either liquids or gases, as well as an erbium-doped fibre amplifier. The fibre amplifier ... -
Photonic Guitar Pick-up: Fiber Strain Sensors Find Applications in Music Recording
(2016-03-07)In this report we give a summary of our work on the development of low-noise fiber-optic strain sensors. Three types of strain sensors were developed and were tested by attaching them to the bodies of acoustic guitars. The ... -
Fabrication and Modeling of Multimode Fiber Lenses
(2016-03-07)We report on the fabrication, modeling, and experimental verification of the emission of fiber lenses fabricated on multimode fibers in different media. Concave fiber lenses with a radius of 150 μm were fabricated onto a ... -
Absorption Measurements in Liquid Core Waveguides Using Cavity
(2016-03-07)Short liquid core waveguides (LCWs) were included into a fiber-loop cavity ring-down absorption spectrometer to reduce the detection limit over, both, single pass absorption in a LCW and cavityenhanced absorption using a ... -
Detection Limits of Chemical Sensors: Applications and Misapplications
(2016-03-08)The limit of detection (LOD) and the sensitivity of a chemical sensor are defined using IUPAC guidelines. The LOD from simulated and experimental data is calculated from a calibration curve using a simple statistical model ... -
Modeling of Fiber-Optic Fluorescence Probes for Strongly Absorbing Samples
(2016-03-08)The dynamic range of fiber-optic fluorescent probes such as single fibers and fiber bundles is calculated for strongly absorbing samples, such as process liquids, foodstuffs, and lubricants. The model assumes an excitation ... -
Fluorescence Excitation–Emission Matrix (EEM) Spectroscopy and Cavity Ring-Down (CRD) Absorption Spectroscopy of Oil-Contaminated Jet Fuel Using Fiber-Optic Probes
(2016-03-11)Excitation emission matrix (EEM) and cavity ring-down (CRD) spectral signatures have been used to detect and quantitatively assess contamination of jet fuels with aero-turbine lubricating oil. The EEM spectrometer has been ... -
Musical Instrument Pickup Based on a Laser Locked to an Optical Fiber Resonator
(2016-03-11)A low-noise transducer based on a fiber Fabry-Perot (FFP) cavity was used as a pickup for an acoustic guitar. A distributed feedback (DFB) laser was locked to a 25 MHz-wide resonance of the FFP cavity using the Pound-Drever-Hall ... -
A Fabry-Perot Refractometer for Chemical Vapor Sensing by Solid-Phase Microextraction
(2016-03-14)The contour lithography method [1] is used to improve the fabrication yield of previously demonstrated [2] microfluidic Fabry-Perot (FP) refractive index (RI) sensors. The sensors are then coated with polydimethylsiloxane ...