Publications associées à Simple harmonic motion

Exciton migration in two-dimensional materials

Excitons play an essential role in the optical response of two-dimensional materials. These are bound states showing up in the band gaps of many-body systems and are conceived as quasiparticles formed by an electron and a hole. By performing real-time simu ...

Nature Portfolio2024

Learning Dynamics of Spring-Mass Models with Physics-Informed Graph Neural Networks

Olga Fink, Vinay Sharma, Manav Manav

We propose a physics-informed message-passing graph neural network (GNN) for learning the dynamics of springmass systems. The proposed method embeds the underlying physics directly into the message-passing scheme of the GNN. We compare the new scheme with ...

Research Publishing2023

A unified framework for Simplicial Kuramoto models

Alexis Arnaudon

Simplicial Kuramoto models have emerged as a diverse and intriguing class of models describing oscillators on simplices rather than nodes. In this paper, we present a unified framework to describe different variants of these models, categorized into three ...

2024

Rapid motion estimation and correction using self-encoded FID navigators in 3D radial MRI

Tobias Kober, Davide Piccini

Purpose: To develop a self-navigated motion compensation strategy for 3D radial MRI that can compensate for continuous head motion by measuring rigid body motion parameters with high temporal resolution from the central k-space acquisition point (self-enco ...

Wiley2023

3D printed fiber-optic nanomechanical bioprobe

Sandor Kasas, Jiangtao Zhou, Yiping Wang, Yuguang Chen

Ultrasensitive nanomechanical instruments, e.g. atomic force microscopy (AFM), can be used to perform delicate biomechanical measurements and reveal the complex mechanical environment of biological processes. However, these instruments are limited because ...

IOP Publishing Ltd2023

Understanding JET-C quiescent phases with edge harmonic magnetohydrodynamic activity and comparison with behaviour under ITER-like wall conditioning

Wilfred Anthony Cooper, Jonathan Graves, Daniele Brunetti, Alberto Mariani, Andreas Kleiner, Guillermo Bustos Ramirez

An analysis of edge localised mode-free (quiescent) H-mode discharges exhibiting edge harmonic magnetoydrodynamic activity in the JET-carbon wall machine is presented. It is observed that the otherwise quiescent pulses with multiple-n harmonic oscillations ...

IOP Publishing Ltd2022

Weak nonlinearity for strong non-normality

François Gallaire, Edouard Boujo, Yves-Marie François Ducimetière

We propose a theoretical approach to derive amplitude equations governing the weakly nonlinear evolution of non-normal dynamical systems, when they experience transient growth or respond to harmonic forcing. This approach reconciles the non-modal nature of ...

Cambridge University Press2022

Anisotropic and nonlinear transport in microstructured 3D topological semimetals

Xiangwei Huang

Topological semimetals are frequently discussed as materials platforms for future electronics that exploit the remarkable properties of their quasiparticles. These ideas are mostly based on dispersion relations that mimic relativistic particles, such as We ...

EPFL2022

On the bulk compressibility of close-packed particles and their composites

Andreas Mortensen, Maria Gabriella Tarantino

The hydrostatic compaction of composites comprising a closely-packed particle-bed filled by a dense matrix is measured experimentally using a fluid-pressurization apparatus. A highly compliant polymer or pure aluminium are infiltrated into preforms of pack ...

ELSEVIER SCI LTD2022

Prospective motion correction in kidney MRI using FID navigators

Tobias Kober

Purpose Abdominal MRI scans may require breath-holding to prevent image quality degradation, which can be challenging for patients, especially children. In this study, we evaluate whether FID navigators can be used to measure and correct for motion prospec ...

WILEY2022

On the interplay effect for moving targets treated with the CyberKnife static tracking system

François Bochud, Yihan Jia

Purpose: To assess the interplay effect amplitude between different planned MU distributions and respiratory patterns in the CyberKnife system when treating moving targets with static tracking technique. Methods: Small-and Large-Respiratory Motions (SRM an ...

2021

Rocker oscillator time bases

Simon Nessim Henein, Ilan Vardi

Since the invention of the pendulum clock by Christiaan Huygens in 1657, precision timekeepers have been regulated by oscillators. Although the pendulum is not an isochronous oscillator, its introduction as a time basis for clock regulation led to a signif ...

2021

Impinging planar jets: hysteretic behaviour and origin of the self-sustained oscillations

Philippe Renaud, François Gallaire, Arnaud Bertsch, Alessandro Bongarzone

The experimental and numerical investigation presented by Bertsch et al. (Phys. Rev. Fluids, vol. 5, 2020a, p. 054202) describes the self-sustained oscillations induced by the interaction of two impinging jets in microfluidic devices. While the oscillatory ...

Cambridge University Press2021

Towards Interactions Through Differentiable-Non-Differentiable Scale Transitions In Scale Relativity Theory

Maria-Alexandra Paun

It is shown that, in the framework of Scale Relativity Theory, correlations of type informational entropy/cross entropy - probability density, in the description of the dynamics of any complex system, can be perceived as interactions. Explaining these inte ...

UNIV POLITEHNICA BUCHAREST, SCI BULL2021

Study of Donor-like Surface Trap Emission in GaN HEMTs

Farzan Jazaeri

Gate-lag induced trapping effects due to donor-like surface traps located in the access regions between the electrodes of AlGaN/GaN HEMTs are investigated through TCAD transient simulations. The effects of variation in trap energy level and temperature on ...

IEEE2021

Nature of Crack Path Instabilities in Thin Sheets Cut by Blunt Objects

Iryna Sivak

Cutting a brittle thin sheet with a blunt object leaves an oscillating crack that seemingly violates the principle of local symmetry for fracture. We experimentally find that at a critical value of a well chosen control parameter the straight propagation i ...

AMER PHYSICAL SOC2020

Teaching optics to a machine learning network

Olivier Martin, André-Pierre Blanchard-Dionne

In this Letter, we demonstrate how harmonic oscillator equations can be integrated in a neural network to improve the spectral response prediction for an optical system. We use the optical properties of a one-dimensional nanoslit array for a practical impl ...

2020

Nonlinear evolution of the centrifugal instability using a semilinear model

François Gallaire, Eunok Yim

We study the nonlinear evolution of the axisymmetric centrifugal instability developing on a columnar anticyclone with a Gaussian angular velocity using a semilinear approach. The model consists of two coupled equations: one for the linear evolution of the ...

Cambridge University Press2020

Optical backaction-evading measurement of a mechanical oscillator

Tobias Kippenberg, Liu Qiu, Itay Shomroni

Quantum mechanics imposes a limit on the precision of a continuous position measurement of a harmonic oscillator, due to backaction arising from quantum fluctuations in the measurement field. This standard quantum limit can be surpassed by monitoring only ...

Springer2019

Eigenmode Analysis in Plasmonics: Application to Second Harmonic Generation and Electron Energy Loss Spectroscopy

Gabriel David Bernasconi

Eigenmodes are central to the study of resonant phenomena in all areas of physics. However, their use in nano-optics seems to have been hindered and delayed for various reasons. First, due to their small size, the response of nanostructures to a far-field ...

EPFL2019