English
Related papers

Related papers: Single-Beam Velocimetry with Dual Frequency Comb A…

200 papers

Accurate knowledge of absorption coefficient of a sample is a prerequisite for measuring the third order optical nonlinearity of materials, which can be a serious limitation for unknown samples. We introduce a method, which measures both…

Optics · Physics 2007-05-23 A. Sharan , S. Abbas Hosseini , D. Goswami

Doubly selective (DS) channel estimation in largescale multiple-input multiple-output (MIMO) systems is a challenging problem due to the requirement of unaffordable pilot overheads and prohibitive complexity. In this paper, we propose a…

Information Theory · Computer Science 2015-11-10 Bo Gong , Qibo Qin , Xiang Ren , Lin Gui , Hanwen Luo , Wen Chen

Investigation of external flows past arbitrary objects requires access to the information in the boundary layer and the inviscid flow to paint a full picture of their characteristics. However, in laser diagnostic techniques such as particle…

Fluid Dynamics · Physics 2023-10-09 Shuangjiu Fu , Shabnam Raayai-Ardakani

We report on the direct measurements of fluid flow vorticity using a spatially shaped beam with a superposition of Laguerre-Gaussian modes that reports on the rotational Doppler shift from microparticles intersecting the beam focus.…

Optics · Physics 2016-06-29 A. Ryabtsev , S. Pouya , A. Safaripour , M. Koochesfahani , M. Dantus

On-chip spectroscopy that could realize real-time fingerprinting with label-free and high-throughput detection of trace molecules is one of the 'holy grails" of sensing. Such miniaturized spectrometers would greatly enable applications in…

Absorption imaging is a commonly adopted method to acquire, with high temporal resolution, spatial information on a partially transparent object. It relies on the interference between a probe beam and the coherent response of the object. In…

Mid-infrared (mid-IR) spectroscopy offers unparalleled sensitivity for the detection of trace gases, solids and liquids, which is based on the existence of strong telltale vibrational bands in this part of the spectrum. It was shown more…

Optics · Physics 2016-08-29 Viktor O. Smolski , Honglei Yang , Jia Xu , Konstantin L. Vodopyanov

Mid-infrared (MIR) spectrometers are invaluable tools for molecular fingerprinting and hyper-spectral imaging. Among the available spectroscopic approaches, GHz MIR dual-comb absorption spectrometers have the potential to simultaneously…

Proton beams generated from laser acceleration show merit for their unique spatial (micron-size) and temporal (picosecond) properties, which make them desirable for many potential applications. However, the large energy spread and…

Accelerator Physics · Physics 2022-09-05 J. G. Zhu , H. Y. Lu , Y. Zhao , M. F. Lai , Y. L. Gu , S. X. Xu , C. T. Zhou

Millimeter wave vehicular channels exhibit structure that can be exploited for beam alignment with fewer channel measurements compared to exhaustive beam search. With fixed layouts of roadside buildings and regular vehicular moving…

Signal Processing · Electrical Eng. & Systems 2024-10-28 Yuyang Wang , Nitin Jonathan Myers , Nuria González-Prelcic , Robert W. Heath

We demonstrate dual-frequency absorption spectroscopy (DFAS) using laser-cooled 87Rb and 85Rb atoms. Doppler-free resonances with high-contrast are produced, which suggest the suitability of using dual-frequency absorption spectroscopy…

Atomic Physics · Physics 2025-08-26 Gour Pati , Mauricio Pulido , Fredrik K. Fatemi , Gustavo Acosta , Renu Tripathi

Dual-comb spectroscopy has been proven a powerful tool in molecular characterization, which remains challenging to implement in the mid-infrared region due to difficulties in the realization of two mutually locked comb sources and efficient…

A room temperature operating Vertical External Cavity Surface Emitting Laser is applied around 1550 nm to intracavity laser absorption spectroscopy analyzed by time-resolved Fourier transform interferometry. At an equivalent pathlength of…

A novel quadrature Doppler Backscattering (DBS) system has been developed and optimized for the E-band (60-90GHz) frequency range using either O-mode or X-mode polarization in DIII-D plasmas. In general, DBS measures the amplitude of…

Dynamic and precise measurement of cerebral blood flow velocity is crucial in neuroscience and the diagnosis of cerebrovascular diseases. Traditional color Doppler ultrasound can only measure the velocity component along the ultrasound…

Medical Physics · Physics 2025-04-25 Shaoyuan Yan , Yiming Ding , Guoao Ma , Yapeng Fu , Kailiang Xu , Dean Ta

This paper investigates three spectroscopic techniques - Tunable Diode Laser Absorption Spectroscopy (TDLAS), Wavelength Modulation Spectroscopy (WMS), and Heterodyne Phase Sensitive Dispersion Spectroscopy (HPSDS) - to evaluate their…

Instrumentation and Detectors · Physics 2025-04-02 Iskander Gazizov , Davide Pinto , Harald Moser , Savda Sam , Pedro Martin-Mateos , Liam O'Faolain , Bernhard Lendl

Despite the dynamic development of computer vision algorithms, the implementation of perception and control systems for autonomous vehicles such as drones and self-driving cars still poses many challenges. A video stream captured by…

Computer Vision and Pattern Recognition · Computer Science 2023-11-14 Piotr Wzorek , Tomasz Kryjak

Imaging systems based on a narrow-band tunable filter are used to obtain Doppler velocity maps of solar features. These velocity maps are created by taking the difference between the blue- and red-wing intensity images of a chosen spectral…

Solar and Stellar Astrophysics · Physics 2010-09-16 Sreejith Padinhatteeri , R. Sridharan , K. Sankarasubramanian

Contrary to conventional frame-based imaging, event-based vision (EBV) or dynamic vision sensing (DVS) asynchronously records binary signals of intensity changes for given pixels with microsecond resolution. The present work explores the…

Fluid Dynamics · Physics 2022-06-22 Christian Willert , Joachim Klinner

This paper presents the design, simulation, and analytical modeling of the single proposed axis MEMSbased capacitive accelerometer. Analytical modeling has been done for frequency and displacement sensitivity. The performance of the…

Systems and Control · Electrical Eng. & Systems 2021-11-09 Veena. S , Newton Rai , H. L. Suresh , Veda Sandeep Nagaraja