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We present a novel high-definition (HD) snapshot diffractive spectral imaging system utilizing a diffractive filter array (DFA) to capture a single image that encodes both spatial and spectral information. This single diffractogram can be…

A minimal solution using two affine correspondences is presented to estimate the common focal length and the fundamental matrix between two semi-calibrated cameras - known intrinsic parameters except a common focal length. To the best of…

Computer Vision and Pattern Recognition · Computer Science 2017-06-07 Daniel Barath , Tekla Toth , Levente Hajder

We report on key signal contributions in photothermal deflection spectroscopy (PDS) of semiconductors at photon energies below the bandgap energy and show how to extract the actual absorption properties from the measurement data. To this…

Materials Science · Physics 2019-07-24 Walter Dickmann , Johannes Dickmann , Florian Feilong Bruns , Stefanie Kroker

The detection of light of thermal origin is the principal means by which humanity has learned about our world and the cosmos. In optical astronomy, in particular, direct detection of thermal photons and the resolution of their spectra have…

Single-shot ultrafast absorbance spectroscopy based on the frequency encoding of the kinetics is analyzed theoretically and implemented experimentally. The kinetics are sampled in the frequency domain using linearly chirped, amplified 33 fs…

In this paper, we report high-precision absolute distance and vibration measurements performed with frequency scanned interferometry. Absolute distance was determined by counting the interference fringes produced while scanning the laser…

Instrumentation and Detectors · Physics 2011-09-13 Hai-Jun Yang , Tianxiang Chen , Keith Riles

The physical principles motivating the Z-scanning laser photoreflectance technique are discussed. The technique is shown to provide a powerful non-contact means to unambiguously characterize electronic transport properties in…

Mesoscale and Nanoscale Physics · Physics 2021-12-08 Will Chism

We propose a new spectroscopic method for measuring weak transitions in cold and trapped atoms, which exploits the long interaction times and tight confinement offered by dark optical traps together with an electron shelving technique to…

Atomic Physics · Physics 2009-09-25 L. Khaykovich , N. Friedman , S. Baluschev , D. Fathi , N. Davidson

Optical imaging quality can be severely degraded by system and sample induced aberrations. Existing adaptive optics systems typically rely on iterative search algorithm to correct for aberrations and improve images. This study demonstrates…

Significant challenges exist in efficient data analysis of most advanced experimental and observational techniques because the collected signals often include unwanted contributions--such as background and signal distortions--that can…

Computer Vision and Pattern Recognition · Computer Science 2025-07-08 Yuan Ni , Zhantao Chen , Alexander N. Petsch , Edmund Xu , Cheng Peng , Alexander I. Kolesnikov , Sugata Chowdhury , Arun Bansil , Jana B. Thayer , Joshua J. Turner

The image subtraction method is a powerful tool to analyze the light variations in crowded fields. This method is able to achieve a nearly optimal differential photometry, even in very dense regions. However, image subtraction is not…

Astrophysics · Physics 2007-05-23 C. Alard

Measurements monitoring the inductive coupling between oscillating radio-frequency magnetic fields and objects of interest create versatile platforms for non-destructive testing. The benefits of ultra low frequency measurements, i.e., below…

Applied Physics · Physics 2024-10-17 L. M. Rushton , L. M. Ellis , J. D. Zipfel , P. Bevington , W. Chalupczak

The performance of nondeterministic nonlinear gates in linear optics relies on the photon counting scheme being employed and the efficiencies of the detectors in such schemes. We assess the performance of the nonlinear sign gate, which is a…

Quantum Physics · Physics 2015-06-26 Stephen D. Bartlett , Eleni Diamanti , Barry C. Sanders , Yoshihisa Yamamoto

We extend the powerful frequency-domain analysis of femtosecond two-photon absorption to the intermediate-field regime, which involves both two- and four-photon transitions. Consequently, we find a broad family of shaped pulses that enhance…

Atomic Physics · Physics 2008-02-20 Lev Chuntonov , Leonid Rybak , Andrey Gandman , Zohar Amitay

Because of its high directivity, free-space optical (FSO) communication offers a number of advantages. It can, however, give rise to major system difficulties concerning alignment between two terminals. During the link-acquisition step…

Signal Processing · Electrical Eng. & Systems 2021-10-06 Hyung-Joo Moon , Hong-Bae Jeon , Chan-Byoung Chae

Distinguishing photon-arrival time and position is crucial for advancing quantum technology. However, capturing spatial and temporal information efficiently remains challenging. Here, we present a novel photon-detection technique to achieve…

Quantum Physics · Physics 2024-07-24 Ozora Iso , Kensuke Miyajima , Ryosuke Shimizu

We measure the temperature dependence of the two-photon absorption and optical Kerr nonlinearity of a silicon waveguide over a range of temperatures from 5.5 to 300 K at a wavelength of 1.55 {\mu}m. The two-photon absorption coefficient is…

Quantum Physics · Physics 2019-05-01 Gary F. Sinclair , Nicola A. Tyler , Döndü Sahin , Jorge Barreto , Mark G. Thompson

Being capable of enhancing the spectral efficiency (SE), faster-than-Nyquist (FTN) signaling is a promising approach for wireless communication systems. This paper investigates the doubly-selective (i.e., time- and frequency-selective)…

Information Theory · Computer Science 2023-05-25 Simin Keykhosravi , Ebrahim Bedeer

Frequency comb absorption spectroscopy combined with low-noise, fast homodyne measurements provide a toolbox for ultra-sensitive absorption measurements. Integrating these schemes on photonic platforms to bring them closer to practical…

Optics · Physics 2023-03-20 Jake Biele , Sabine Wollmann , Euan Allen

Context. Solar Shack-Hartmann wavefront sensors measure differential wavefront tilts as the relative shift between images from different subapertures. There are several methods in use for measuring these shifts. Aims. We evaluate the…

Instrumentation and Methods for Astrophysics · Physics 2015-05-20 Mats G. Löfdahl