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Herein, the concept of point of darkness based on polarized light phase difference and absorption of light is demonstrated by simulations using low refractive index and extinction coefficient semiconductor and dielectric, and high…

Optics · Physics 2022-02-17 Ilze Aulika , Martins Zubkins , Jelena Butikova , Juris Purans

We study pressure acoustic propagation in asymmetric spoof-fluid-spoof acoustic waveguides and its potential application in acoustic gas sensors. First, a stable and efficient analytical method is established for fast calculation of the…

This paper describes a completely new way to perform noise rejection using a two-photon sensitive detector and taking advantage of the properties of correlated photons to improve an optical communications link in the presence of…

Instrumentation and Detectors · Physics 2015-06-26 Deborah J. Jackson , George M. Hockney , Jonathan P. Dowling

Two large-area, low noise, high speed fluorescence detectors have been built. One detector consists of a photodiode with an area of 28 mm x 28 mm and a low noise transimpedance amplifier. This detector has a input light-equivalent spectral…

Atomic Physics · Physics 2009-11-11 S. Bickman , D. DeMille

This paper reports the first gas sensor based on the plastic inorganic semiconductor GaPS4, pioneering the application of plastic inorganic semiconductors in the field of gas sensing. Unlike traditional rigid sensors, this device leverages…

Chemical Physics · Physics 2025-11-27 Qiao Wang

We design, test, and analyze fiber-optic voltage sensors based on optical reflection from a piezoelectric transducer. By controlling the physical dimensions of the device, we can tune the frequency of its natural resonance to achieve a…

Systems and Control · Electrical Eng. & Systems 2021-08-02 Joseph M. Lukens , Nicholas Lagakos , Victor Kaybulkin , Christopher J. Vizas , Daniel J. King

Noise pollution investigation takes advantage of two common methods of diagnosis: measurement using a Sound Level Meter and acoustical imaging. The former enables a detailed analysis of the surrounding noise spectrum whereas the latter is…

Instrumentation and Detectors · Physics 2016-03-28 Charles Vanwynsberghe , Régis Marchiano , François Ollivier , Pascal Challande , Hélène Moingeon , Jacques Marchal

Broadband infrared photodetectors have profound importance in diverse applications including security, gas sensing, bioimaging, spectroscopy for food quality, and recycling, just to name a few. Yet, these applications can currently be…

Applied Physics · Physics 2022-03-28 Biswajit Kundu , Onur Özdemir , Mariona Dalmases , Gaurav Kumar , Gerasimos Konstantatos

By exploiting the quantised nature of light, we demonstrate a sub-shot-noise scanning optical transmittance microscope. Our microscope demonstrates, with micron scale resolution, a factor of improvement in precision of 1.76(9) in…

Raman spectroscopy enables broadband, multi-species gas analysis by providing access to an entire vibrational spectrum in a single measurement. However, the sensitivity of gas-phase Raman sensing is often limited by weak signals and…

We demonstrate coherent dual frequency-comb spectroscopy for detecting variations in greenhouse gases. High signal-to-noise spectra are acquired spanning 5990 to 6260 cm^-1 (1600 to 1670 nm) covering ~700 absorption features from CO2, CH4,…

We present results on the fabrication of chemiresistive nanocomposite NiO:Pd hydrogen sensors, which are able to detect hydrogen concentrations as low as 300 ppb in air, operating at temperatures in the 115-145 C range. Thin NiO films were…

Materials Science · Physics 2014-01-22 M. Kandyla , C. Chatzimanolis-Moustakas , M. Guziewicz , M. Kompitsas

A Large Area Avalanche Photodiode (LAAPD) was studied, aiming to access its performance as light detector at low temperatures, down to -80 C. The excess noise factor, F, was measured and found to be approximately independent of the…

Instrumentation and Detectors · Physics 2009-11-07 V. N. Solovov , F. Neves , V. Chepel , M. I. Lopes , R. F. Marques , A. J. P. L. Policarpo

A new instrument for spot profile analysis of electron diffraction - SPA-LEED - has been set up. The instrument works either with a transparent phosphor screen for visual inspection of the pattern or in its main mode with a channeltron for…

Materials Science · Physics 2015-01-30 U. Scheithauer , G. Meyer , M. Henzler

Background-free fluorescence detection in multidimensional electronic spectroscopy promises high sensitivity compared to conventional approaches. Here we explore the sensitivity limits of multidimensional electronic spectroscopy. We present…

Chemical Physics · Physics 2022-10-18 Amitav Sahu , Vivek N. Bhat , Sanjoy Patra , Vivek Tiwari

Continuous monitoring of voltages ranging from tens to hundreds of kV over environmental conditions, such as temperature, is of great interest in power grid applications. This is typically done via instrument transformers. These…

Studies of biological solutions require high measurement accuracy, the ability to detect low changes in substance concentration, and small amounts of the liquid under test. A microwave complex permittivity measurement technique based on a…

Micro and nanoscale particles are crucial in various fields, from biomedical imaging to environmental processes. While conventional spectroscopy and microscopy methods for characterizing these particles often involve bulky equipment and…

Biological Physics · Physics 2024-11-26 Jie Liao , Maxwell Adolphson , Hangyue Li , Dipayon Kumar Sikder , Chenyang Lu , Lan Yang

In order to enhance LIDAR performance metrics such as target detection sensitivity, noise resilience and ranging accuracy, we exploit the strong temporal correlation within the photon pairs generated in continuous-wave pumped semiconductor…

The applications of automotive cameras in Advanced Driver-Assistance Systems (ADAS) are growing rapidly as automotive manufacturers strive to provide 360 degree protection for their customers. Vision systems must capture high quality images…

Image and Video Processing · Electrical Eng. & Systems 2020-11-26 Shane Gilroy , John O'Dwyer , Lucas Bortoleto