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Over the last two decades, spatial light modulators (SLMs) have revolutionised our ability to shape optical fields. They grant independent dynamic control over thousands of degrees-of-freedom within a single light beam. In this work we test…

A fraction of Galactic stars have compact companions which could be white dwarfs (WDs), neutron stars (NSs) or stellar-mass black holes (SBHs). In a detached and edge-on binary system including a main-sequence star and a compact object…

Solar and Stellar Astrophysics · Physics 2024-09-20 Sedighe Sajadian , Niayesh Afshordi

Both lucky imaging techniques and adaptive optics require natural guide stars, limiting sky coverage, even when laser guide stars are used. Lucky imaging techniques become less successful on larger telescopes unless adaptive optics is used,…

Instrumentation and Methods for Astrophysics · Physics 2015-06-19 Alastair Basden

The mid-infrared spectral window is essential for molecular fingerprinting and atmospheric sensing, yet unlocking its full potential is currently constrained by a fundamental instrumental trade-off: existing systems cannot simultaneously…

The metal line profiles of different ions observed in high HI column density systems [N(HI) > 10^{16} cm^{-2}] in quasar spectra can be used to constrain the ionization structure and kinematic characteristics of the absorbers. For these…

Astrophysics · Physics 2009-11-07 S. A. Levshakov , I. I. Agafonova , M. Centurion , I. E. Mazets

We present a method to determine sodium-abundance ratios ([Na/Fe]) using the Na I D doublet lines in low-resolution ($R \sim$ 2000) stellar spectra. As stellar Na I D lines are blended with those produced by the interstellar medium (ISM),…

Astrophysics of Galaxies · Physics 2022-02-02 Jae-Rim Koo , Young Sun Lee , Hye-Jin Park , Young Kwang Kim , Timothy C. Beers

We use an airborne pulsed integrated path differential absorption lidar to make spectroscopic measurements of the pressure-induced line broadening and line center shift of atmospheric CO2 at the 1572.335 nm absorption line. We measure the…

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…

Optics · Physics 2018-08-09 E. A. Tikhonov , V. P. Yashchuk , G. M. Telbiz

Light detection and ranging (LiDAR) have emerged as a crucial tool for high-resolution 3D imaging, particularly in autonomous vehicles, remote sensing, and augmented reality. However, the increasing demand for faster acquisition speed and…

Optics · Physics 2025-07-28 Yixiu Shen , Zi Heng Lim , Guangya Zhou

A simple yet precise optical technique for measuring the ambipolar carrier mobility in semiconductors is presented. Using tightly focused Gaussian laser beams in a photo-reflectance system, the modulated reflectance signal is measured as a…

Instrumentation and Detectors · Physics 2017-11-06 Will Chism

We demonstrate a method to double the collection efficiency in Laser Tweezers Raman Spectroscopy (LTRS) by collecting both the forward and back-scattered light in a single-shot multitrack measurement. Our method can collect signals at…

Optics · Physics 2021-06-09 Tobias Dahlberg , Magnus Andersson

The solar spectrum is a primary reference for the study of physical processes in stars and their variation during activity cycles. In Nov 2010 an experiment with a prototype of a Laser Frequency Comb (LFC) calibration system was performed…

We optimize modulation formats for the additive white Gaussian noise channel with a nonnegative input constraint, also known as the intensity-modulated direct detection channel, with and without confining them to a lattice structure. Our…

Information Theory · Computer Science 2015-03-19 Johnny Karout , Erik Agrell , Krzysztof Szczerba , Magnus Karlsson

We report on an attempt to generate highly stable continuous terahertz (THz) wave by using optical frequency comb (OFC). About 10-nm wide OFC has been generated through a deep phase modulation of a 852 nm laser line in lithium niobate…

We exploit millimeter wave technology to measure the reflection and transmission response of random dielectric media. Our samples are easily constructed from random stacks of identical, sub-wavelength quartz and Teflon wafers. The…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 John A. Scales , L. D. Carr , D. B. McIntosh , Valentin Freilikher , Yu. P. Bliokh

Millimetre-wave observations represent an important tool for Cosmology studies. The Line Intensity Mapping (LIM) technique has been proposed to map in three dimensions the specific intensity due to line (e.g. [CII], CO) emission, for…

Instrumentation and Methods for Astrophysics · Physics 2023-08-29 Usasi Chowdhury , Florence Levy-Bertrand , Martino Calvo , Johannes Goupy , Alessandro Monfardini

We present a high-power continuous-wave (CW) lunar laser ranging (LLR) technique that has the potential to significantly improve Earth--Moon distance measurements. Using a 1 kW CW laser at 1064 nm and a 1 m-aperture telescope as an example,…

Instrumentation and Methods for Astrophysics · Physics 2025-07-01 Slava G. Turyshev

Line intensity mapping (LIM) is an emerging observational method to study the large-scale structure of the Universe and its evolution. LIM does not resolve individual sources but probes the fluctuations of integrated line emissions. A…

Astrophysics of Galaxies · Physics 2020-06-03 Kana Moriwaki , Nina Filippova , Masato Shirasaki , Naoki Yoshida

We report a 4.9\,ppb measurement of the positronium $\text{1}^\text{3}\text{S}_\text{1} \to \text{2}^\text{3}\text{S}_\text{1}$ interval using continuous-wave two-photon laser spectroscopy. The transition is detected via photoionization by…

Atomic Physics · Physics 2025-12-19 Lucas de Sousa Borges , Edward Thorpe-Woods , Evans Javary , Paolo Crivelli

Holographic light potentials generated by phase-modulating liquid-crystal spatial light modulators (SLMs) are widely used in quantum technology applications. Accurate calibration of the wavefront and intensity profile of the laser beam at…

Optics · Physics 2025-06-13 P. Schroff , E. Haller , S. Kuhr , A. La Rooij