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We apply the multigrid-reduction-in-time (MGRIT) algorithm to an eddy current simulation of a two-dimensional induction machine supplied by a pulse-width-modulation signal. To resolve the fast-switching excitations, small time steps are…

Numerical Analysis · Mathematics 2020-06-30 Matthias Bolten , Stephanie Friedhoff , Jens Hahne , Sebastian Schöps

An imaging system is proposed for matter-wave functions that is based on producing a quadratic phase modulation on the wavefunction of a charged particle, analogous to that produced by a space or time lens. The modulation is produced by…

Quantum Physics · Physics 2020-10-28 Brian H. Kolner

In Impulsive Stimulated Raman Scattering vibrational oscillations, coherently stimulated by a femtosecond Raman pulse, are real time monitored and read out as intensity modulations in the transmission of a temporally delayed probe pulse.…

Chemical Physics · Physics 2019-11-28 Giovanni Batignani , Carino Ferrante , Giuseppe Fumero , Tullio Scopigno

The introduction of time as an additional degree of freedom to control wave-matter interactions have opened new avenues to fully control wave propagation in four dimensions (x,y,z,t). Time interfaces (rapid changes of the constitutive…

Optics · Physics 2024-12-03 Mariya Antyufeyeva , Victor Pacheco-Peña

We present a new spatial-spectral mapping technique permitting to measure the beam intensity at the output of a graded-index (GRIN) multimode fiber with sub-nanometric spectral resolution. We apply this method to visualize the fine…

Users' desire for enhanced performance drive the inevitable technological progress on vertical applications in wireless communication systems. To meet these demands, researchers vigorously investigate potential 6G and beyond technologies…

Signal Processing · Electrical Eng. & Systems 2024-07-15 Emre Arslan , Ali Tugberk Dogukan , Fatih Kilinc , Ertugrul Basar

Physics-Informed Neural Networks (PINNs) have gained significant attention for their simplicity and flexibility in engineering and scientific computing. In this study, we introduce a normalized PINN (NPINN) framework to solve a class of…

Numerical Analysis · Mathematics 2025-03-11 Jichao Ma , Dandan Liu , Jinran Wu , Xi'an Li

In various applications, the multivariate time series often suffers from missing data. This issue can significantly disrupt systems that rely on the data. Spatial and temporal dependencies can be leveraged to impute the missing samples.…

Machine Learning · Computer Science 2025-05-06 Amir Eskandari , Aman Anand , Drishti Sharma , Farhana Zulkernine

Graph signal processing (GSP) has emerged as a powerful framework for analyzing data on irregular domains. In recent years, many classical techniques in signal processing (SP) have been successfully extended to GSP. Among them, chirp…

Signal Processing · Electrical Eng. & Systems 2025-08-01 Manjun Cui , Zhichao Zhang , Wei Yao

Compressed sensing has shown great potential in reducing data acquisition time in magnetic resonance imaging (MRI). Recently, a spread spectrum compressed sensing MRI method modulates an image with a quadratic phase. It performs better than…

Computer Vision and Pattern Recognition · Computer Science 2016-01-27 Xiaobo Qu , Ying Chen , Xiaoxing Zhuang , Zhiyu Yan , Di Guo , Zhong Chen

We propose a new method for implementing mutually unbiased generation and measurement of time-bin qudits using a cascade of electro-optic phase modulator -- coded fiber Bragg grating pairs. Our approach requires only a single spatial mode…

Quantum Physics · Physics 2018-03-16 Joseph M. Lukens , Nurul T. Islam , Charles Ci Wen Lim , Daniel J. Gauthier

Dynamic modulation of material properties in space and time enables powerful control over wave propagation, yet existing theories largely rely on idealized, nondispersive models. In realistic media, frequency dispersion can strongly reshape…

Optics · Physics 2026-04-02 Klaas De Kinder , Christophe Caloz

The application of deep learning methods to speed up the resolution of challenging power flow problems has recently shown very encouraging results. However, power system dynamics are not snap-shot, steady-state operations. These dynamics…

Machine Learning · Computer Science 2022-06-22 Mostafa Mohammadian , Kyri Baker , Ferdinando Fioretto

In this paper, a time-periodic MGRIT algorithm is proposed as a means to reduce the time-to-solution of numerical algorithms by exploiting the time periodicity inherent to many applications in science and engineering. The time-periodic…

Computational Engineering, Finance, and Science · Computer Science 2022-01-12 Andreas Hessenthaler , Robert D. Falgout , Jacob B. Schroder , Adelaide de Vecchi , David Nordsletten , Oliver Röhrle

Time has emerged as a new degree of freedom for metamaterials, promising new pathways in wave control. However, electromagnetism suffers from limitations in the modulation speed of material parameters. Here we argue that these limitations…

Mesoscale and Nanoscale Physics · Physics 2019-11-20 E. Galiffi , P. A. Huidobro , J. B. Pendry

The Gradient Ascent Pulse Engineering (GRAPE) is a celebrated control algorithm with excellent converging rates, owing to a piece-wise-constant ansatz for the control function that allows for cheap objective gradients. However, the…

Quantum Physics · Physics 2021-02-17 Martin Larocca , Diego Wisniacki

Homogenization of a thin micro-structure yields effective jump conditions that incorporate the geometrical features of the scatterers. These jump conditions apply across a thin but nonzero thickness interface whose interior is disregarded.…

Computational Physics · Physics 2017-03-08 Bruno Lombard , Agnes Maurel , Jean-Jacques Marigo

Real-space grids are a powerful alternative for the simulation of electronic systems. One of the main advantages of the approach is the flexibility and simplicity of working directly in real space where the different fields are discretized…

This study introduces the Bragg Frequency Convertor, a spatial-temporal-periodic grating that extends the concept of conventional Bragg gratings into the dynamic domain to achieve pure parametric frequency conversion. By time-modulating…

Optics · Physics 2026-03-10 Sajjad Taravati

The Generalized Integral Representation Method (GIRM) for Space-Time-Separated Method (STSM) and Space-Time-Unified Method (STUM) are discussed. STSM and STUM give explicit and implicit time evolutions, respectively. The algorithm of STSM…

Numerical Analysis · Mathematics 2017-07-18 Hiroshi Isshiki , Daisuke Kitazawa