English
Related papers

Related papers: Steady-periodic method for modeling mode instabili…

200 papers

We report the observation of the thermalization of the Fermi-Pasta-Ulam-Tsingou recurrence process in optical fibers. We show the transition from a reversible regime to an irreversible one, revealing a spectrally thermalized state. To do…

Pattern Formation and Solitons · Physics 2022-10-12 Guillaume Vanderhaegen , Pascal Szriftgiser , Alexandre Kudlinski , Matteo Conforti , Andrea Armaroli , Arnaud Mussot

The energy transition is causing many stability-related challenges for power systems. Transient stability refers to the ability of a power grid's bus angles to retain synchronism after the occurrence of a major fault. In this paper a…

Optimization and Control · Mathematics 2021-01-12 Tim Aschenbruck , Willem Esterhuizen , Stefan Streif

We present a simple method to stabilize the optical path length of an optical fiber to an accuracy of about 1/100 of the laser wavelength. We study the dynamic response of the path length to modulation of an electrically conductive heater…

Optics · Physics 2007-05-23 Holger Mueller , Achim Peters , Claus Braxmaier

We study initial transient stages in directional solidification by means of a non-variational phase field model with fluctuations. This model applies for the symmetric solidification of dilute binary solutions and does not invoke…

Materials Science · Physics 2016-08-16 R. Benítez , L. Ramírez-Piscina

We present a family of integral equation-based solvers for the linear or semilinear heat equation in complicated moving (or stationary) geometries. This approach has significant advantages over more standard finite element or finite…

Numerical Analysis · Mathematics 2022-12-06 Jun Wang , Leslie Greengard , Shidong Jiang , Shravan Veerapaneni

We propose a time-adaptive predictor/multi-corrector method to solve hyperbolic partial differential equations, based on the generalized-$\alpha$ scheme that provides user-control on the numerical dissipation and second-order accuracy in…

Numerical Analysis · Mathematics 2022-10-11 Nicolas A. Labanda , Pouria Behnoudfar , Victor M. Calo

Floquet engineering offers a powerful route to enhance emission in time-modulated media. Here, we investigate the influence of time-modulated permittivity in silicon carbide on its intensity spectrum. We consider both the nonequilibrium…

Mesoscale and Nanoscale Physics · Physics 2026-02-27 Yuhua Ren , Hui Pan , Jian-Sheng Wang

The resonance wavelength, where a fiber mode converter grating written using periodic external perturbations achieves phase matching, is both a critical design parameter and a device parameter. However, a method to precisely predict the…

Optics · Physics 2020-10-14 Soham Basu

We study reheating in some one and two field realizations of {\it Fibre Inflation}. We find that reheating begins with a phase of preheating in which long wavelength fluctuation modes are excited. In two field models there is a danger that…

High Energy Physics - Theory · Physics 2018-09-05 Bao-Min Gu , Robert Brandenberger

An equation based reduced order model applicable to generalized heat equation and thermal simulations of power electronics systems developed in commercial CFD tools, is presented in this work. The model considers the physics of heat…

Numerical Analysis · Mathematics 2024-04-26 Neelakantan Padmanabhan

The evolution of multi-mode instabilities in a hypersonic boundary layer and their effects on aerodynamic heating are investigated. Experiments are conducted in a Mach 6 wind tunnel using Rayleigh-scattering flow visualization,…

Fluid Dynamics · Physics 2016-07-04 Yiding Zhu , Xi Chen , Jiezhi Wu , Shiyi Chen , Cunbiao Lee , Mohamed Gad-el-Hak

Computing solutions to partial differential equations using the fast Fourier transform can lead to unwanted oscillatory behavior. Due to the periodic nature of the discrete Fourier transform, waves that leave the computational domain on one…

Numerical Analysis · Mathematics 2023-01-18 Anne Liu , Thomas Trogdon

We enhance optical network availability and reliability through a lightweight transformer model that predicts optical fiber amplifier lifetime from condition-based monitoring data, enabling real-time, edge-level predictive maintenance and…

Signal Processing · Electrical Eng. & Systems 2026-03-31 Dominic Schneider , Lutz Rapp , Christoph Ament

We developed an improved model in order to predict the RF behavior and the slow light properties of the SOA valid for any experimental conditions. It takes into account the dynamic saturation of the SOA, which can be fully characterized by…

The forced time harmonic response of a spatiotemporally-modulated elastic beam of finite length with light damping is derived using a novel Green's function approach. Closed-form solutions are found that highlight unique mode coupling…

Applied Physics · Physics 2024-09-05 Benjamin M. Goldsberry , Andrew N. Norris , Samuel P. Wallen , Michael R. Haberman

A theoretical model is developed by exploiting the variational technique to investigate the evolution of an optical beam inside an optically pumped graded-index fiber amplifier. The variational analysis is a semi-analytical method that…

Optics · Physics 2023-10-24 Anuj P. Lara , Samudra Roy , Govind P. Agrawal

We study the time-dependent transport of heat in a nanoscale thermal switch. The switch consists of left and right leads that are initially uncoupled. During switch-on the coupling between the leads is abruptly turned on. We use the…

Mesoscale and Nanoscale Physics · Physics 2010-02-10 Eduardo C. Cuansing , Jian-Sheng Wang

We show that instantaneous spatial singular modes of light in a dynamically evolving, turbulent atmosphere offer significantly improved high-fidelity signal transmission as compared to standard encoding bases corrected by adaptive optics.…

We introduce an experimental technique for complete phase-sensitive characterization of arbitrary unitary spectral-temporal transformations of optical modes. Our method recovers the complex spectral transfer function, or Green's function,…

This work presents a review on the effect of transverse mode instability in high-power fiber laser systems and the corresponding investigations led worldwide over the last decade. This manuscript includes the description of the experimental…

Optics · Physics 2020-05-01 Cesar Jauregui , Christoph Stihler , Jens Limpert