Related papers: A Novel Compact and Selective Gas Sensing System B…
A high-sensitivity LED based photoacoustic NO$_2$ sensor is demonstrated. Sensitive photoacoustic gas sensors based on incoherent light sources are typically limited by background noise and drifts due to a strong signal generated by light…
Optical emission spectroscopy from a small-volume, 5 uL, atmospheric pressure RF-driven helium plasma was used in conjunction with Partial Least Squares Discriminant Analysis (PLS-DA) for the detection of trace concentrations of methane…
We introduce optical polarization-insensitive high pass filters based on total internal reflection of light at the interface of two dielectric media (1D) and Bragg reflection of a multilayer stack (2D) in transmission mode. The wavevectors…
The synthesis of multiple narrow optical spectral lines, precisely and independently tuned across the near- to mid-infrared (IR) region, is a pivotal research area that enables selective and real-time detection of trace gas species within…
Intracellular lasers are emerging as powerful biosensors for multiplexed tracking and precision sensing of cells and their microenvironment. This sensing capacity is enabled by quantifying their narrow-linewidth emission spectra, which is…
We review an on-chip approach for spontaneous Raman spectroscopy and Surface Enhanced Raman Spectroscopy (SERS) based on evanescent excitation of the analyte as well as evanescent collection of the Raman signal using Complementary Metal…
Dye-doped hybrid silicate/titanium nanofilms on the glass substrate in the structure of asymmetrical waveguides were studied as the laser system. The spatial and spectral features of laser oscillation of genuine and hollow waveguides were…
A novel methodology for measuring gas flow from small orifices or nozzles into vacuum is presented. It utilizes a high-intensity femtosecond laser pulse to create a plasma within the gas plume produced by the nozzle, which is imaged by a…
Laser guide stars created by Rayleigh scattering provide a reasonable means to monitor atmospheric wavefront distortions for real-time correction by adaptive optics systems. Because of the $\lambda^{-4}$ wavelength dependence of Rayleigh…
We study the surface modes of a homogeneous spherical gain medium and provide a comprehensive analytic treatment of a special class of these modes that support spectral singularities. Because the latter have a divergent quality factor, we…
Semiconductor lasers with ultra-low thresholds and minimal footprints are a topic of active research. Such devices require a combination of high quality factor laser cavities with small active region volumes, which drives the quest for…
Identification of non-amplified DNA sequences and single-base mutations is essential for molecular biology and genetic diagnostics. This paper reports a novel sensor consisting of electrochemically-gated graphene coplanar waveguides coupled…
Short-length fiber lasers are key elements for device integration in fiber systems. However, efficiently absorbing a pump beam in a short ion-doped fiber remains a challenge. We present an approach that renders a weakly absorbing…
Sparse wideband sensor array design for sensor location optimisation is highly nonlinear and it is traditionally solved by genetic algorithms, simulated annealing or other similar optimization methods. However, this is an extremely…
The remote sensing of gases in complex mixtures at atmospheric pressure is a challenging problem and much attention has been paid to it. The most fundamental difference between this application and highly successful astrophysical and upper…
Here we demonstrate the gas sensing ability of cavity-coupled metallic nanoparticle systems, comprising gold nanoparticles separated from a gold mirror with a polymer spacer. An increase in relative humidity (RH) causes the spacer to…
We present detailed experimental and numerical studies of random lasing in weakly scattering systems. The interference of scattered light, which is weak in the passive systems, is greatly enhanced in the presence of high gain, providing…
Large array gas detector systems are used in particle and nuclear physics experiments involving high-energy nucleon-nucleon and heavy-ion collisions. We have observed that in large array gas detector systems the momentary discharges inside…
Whispering gallery mode (WGM) laser sensors, utilizing the interaction between the in-plane evanescent field and the surface vicinity, provide enhanced sensitivity in label-free sensing for bioanalysis and disease screening. However, the…
Advances in the technologies associated with position sensitive gaseous detectors especially featuring CsI as reflective photoconverters will be reviewed. These photodetectors represent the most effective solution for what concerns cost and…