English
Related papers

Related papers: Numerical Method for Nonlinear Optical Spectroscop…

200 papers

Optical spectroscopy of molecular radicals is an important tool in physical chemistry, and is a prerequisite for many experiments which use molecules for quantum science and precision measurement. However, even the simplest molecules have…

Chemical Physics · Physics 2025-05-07 Ashay N. Patel , Madison I. Howard , Timothy C. Steimle , Nicholas R. Hutzler

The absorption of broadband photons in atomic ensembles requires either an effective broadening of the atomic transition linewidth, or an off-resonance Raman interaction. Here we propose a scheme for a quantum memory capable of storing and…

Quantum Physics · Physics 2017-01-18 G. S. Thekkadath , K. Heshami , D. G. England , P. J. Bustard , B. J. Sussman , M. Spanner

Image reconstruction from radio-frequency data is pivotal in ultrafast plane wave ultrasound imaging. Unlike the conventional delay-and-sum (DAS) technique, which relies on somewhat imprecise assumptions, deep learning-based methods perform…

Computer Vision and Pattern Recognition · Computer Science 2023-12-18 Hengrong Lan , Zhiqiang Li , Qiong He , Jianwen Luo

We present a new algorithm to rapidly and optimally compute power spectra. This new algorithm is based on a generalization of iterative multigrid, and has computational cost O(N log N), compared to the standard brute force approach which…

Astrophysics · Physics 2009-11-07 Ue-Li Pen

We describe an experiment to measure the emitted real-time electric field from an ultrafast third-order nonlinear optical interaction in molecules, using a phase-tracked spectral interferometry scheme. By combining a software lock-in…

Optics · Physics 2025-03-11 Siddhant Pandey , Francis Walz , Niranjan Shivaram

This paper presents a fast and powerful method for the computation of eigenvalue bounds for Hessian matrices $\nabla^2 \varphi(x) $ of nonlinear functions $\varphi: U \subseteq R^n\rightarrow R$ on hyperrectangles $B \subset U$. The method…

Optimization and Control · Mathematics 2015-07-23 Moritz Schulze Darup , Martin Mönnigmann

We developed a novel technique for frequency measurement and synthesis, based on the operation of a femtosecond comb generator as transfer oscillator. The technique can be used to measure frequency ratios of any optical signals throughout…

Optics · Physics 2009-11-07 Jörn Stenger , Harald Schnatz , Christian Tamm , Harald R. Telle

This paper presents a fast spectral unmixing algorithm based on Dykstra's alternating projection. The proposed algorithm formulates the fully constrained least squares optimization problem associated with the spectral unmixing task as an…

Computer Vision and Pattern Recognition · Computer Science 2015-05-08 Qi Wei , Jose Bioucas-Dias , Nicolas Dobigeon , Jean-Yves Tourneret

Attosecond nonlinear Fourier transform (NFT) pump probe spectroscopy is an experimental technique which allows investigation of the electronic excitation, ionization, and unimolecular dissociation processes. The NFT spectroscopy utilizes…

Chemical Physics · Physics 2021-02-11 Sergy Grebenshchikov , Sergio Carbajo

This paper describes an efficient algorithm for computing steady two-dimensional surface gravity wave in irrotational motion. The algorithm complexity is O(N log N), N being the number of Fourier modes. The algorithm allows the arbitrary…

Classical Physics · Physics 2020-02-20 Didier Clamond , Denys Dutykh

The fast algorithms in Fourier optics have invigorated multifunctional device design and advanced imaging technologies. However, the necessity for fast computations has led to limitations in the widely used conventional Fourier methods,…

Applied Physics · Physics 2024-06-25 Zhi Li , Xuhao Luo , Jing Wang , Xin Yuan , Dongdong Teng , Qiang Song , Huigao Duan

The special unitary group SU(2) plays a fundamental role in the description of symmetries in quantum mechanics, theoretical physics, and spherical signal processing. In this paper, we address the computational challenges of performing…

Computational Physics · Physics 2026-05-26 Julio Delgado , Alejandro Umaña

In portable, 3-D, or ultra-fast ultrasound (US) imaging systems, there is an increasing demand to reconstruct high quality images from limited number of data. However, the existing solutions require either hardware changes or…

Computer Vision and Pattern Recognition · Computer Science 2017-10-31 Yeo Hun Yoon , Jong Chul Ye

This paper proposes a method for estimating and detecting optical signals in practical photon-counting receivers. There are two important aspects of non-perfect photon-counting receivers, namely, (i) dead time which results in blocking…

Signal Processing · Electrical Eng. & Systems 2024-08-21 Chen Wang , Zhiyong Xu , Jingyuan Wang , Jianhua Li , Weifeng Mou , Huatao Zhu , Jiyong Zhao , Yang Su , Yimin Wang , Ailin Qi

This paper introduces a novel method for the automatic detection and handling of nonlinearities in a generic transformation. A nonlinearity index that exploits second order Taylor expansions and polynomial bounding techniques is first…

Numerical Analysis · Mathematics 2024-02-05 Matteo Losacco , Alberto Fossà , Roberto Armellin

One of the challenges in hyperspectral data analysis is the presence of mixed pixels. Mixed pixels are the result of low spatial resolution of hyperspectral sensors. Spectral unmixing methods decompose a mixed pixel into a set of endmembers…

Computer Vision and Pattern Recognition · Computer Science 2015-06-05 Roozbeh Rajabi , Hassan Ghassemian

A simple least-squares optimisation enables the determination of the spectrum for irregularly sampled data that is readily reconstructed using an adjoint transformation of the Non-Uniform Fast Fourier Transform (NFFT). This is an…

Numerical Analysis · Mathematics 2024-02-28 Michael Sorochan Armstrong , José Carlos Pérez-Girón , José Camacho , Regino Zamora

A fast and accurate computational scheme for simulating nonlinear dynamic systems is presented. The scheme assumes that the system can be represented by a combination of components of only two different types: first-order low-pass filters…

Quantitative Methods · Quantitative Biology 2008-06-20 J. H. van Hateren

The discovery and understanding of many ultrafast dynamical processes are often invaluable. This paper is the first report to apply optical parametric amplification to implement single-shot ultrafast imaging with high space and time…

Simulated wide-field images are becoming an important part of observational astronomy, either to prepare for new surveys or to test measurement methods. In order to efficiently explore vast parameter spaces, the computational speed of…

Instrumentation and Methods for Astrophysics · Physics 2012-09-07 Joel Bergé , Lukas Gamper , Alexandre Réfrégier , Adam Amara
‹ Prev 1 4 5 6 7 8 10 Next ›