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Concept

Onde de Rayleigh

Publications associées (27)

Optothermal shaping of lamb waves with square and spiral phase fronts

Romain Christophe Rémy Fleury, Aleksi Antoine Bossart, Janez Rus

We introduce a Lamb-wave medium with tunable propagation velocities, which are controlled by a two-dimensional heating pattern produced by a laser beam. We utilized it to demonstrate that waves in an appropriately designed medium can propagate in the form ...

2024

Frictional weakening leads to unconventional singularities during dynamic rupture propagation

Marie Estelle Solange Violay, François Xavier Thibault Passelègue, Mathias Alexandre David Lebihain, Federica Paglialunga

Earthquakes i.e. frictional ruptures, are commonly described by singular solutions of shear crack motions. These solutions assume a square root singularity order around the rupture tip and a constant shear stress value behind it, implying scale-independent ...

2024

In-Sensor Passive Speech Classification with Phononic Metamaterials

Luis Guillermo Villanueva Torrijo, Daniel Moreno Garcia

Mitigating the energy requirements of artificial intelligence requires novel physical substrates for computation. Phononic metamaterials have vanishingly low power dissipation and hence are a prime candidate for green, always-on computers. However, their u ...

Wiley-V C H Verlag Gmbh2024

Automatic and high-precision microseismic monitoring of progressive failure prior, during, and after tunnel excavation

Brice Tanguy Alphonse Lecampion, Seyyedmaalek Momeni, Christophe Nussbaum

Acoustic emission (AE) monitoring is commonly used to inspect the health of a structure continuously. During fracture processes elastic waves of AE are created and emitted, and sensors can capture these waves. The acquired signals can be processed to track ...

2023

Long-distance coherent propagation of magnon polarons in a ferroelectric-ferromagnetic heterostructure

Jean-Philippe Ansermet, Haiming Yu, Peng Chen

We experimentally demonstrate the coherent propagation of magnon polarons, the hybridized excitations formed by the coupling of spin waves and Rayleigh/Love surface acoustic waves, in a heterostructure consisting of ferroelectric BaTiO3 and ferromagnetic L ...

Amer Physical Soc2023

Automatic and high-precision acoustic emission-based structural health monitoring of concrete structures

Brice Tanguy Alphonse Lecampion, Seyyedmaalek Momeni

Acoustic emission (AE) monitoring is a useful technique to monitor the health of a structure continuously, helping to prevent potential failure. AE are elastic waves produced and emitted during fracture processes inside a material and are recorded by senso ...

DESTech publications inc.2023

Toward Band n78 Shear Bulk Acoustic Resonators Using Crystalline Y-Cut Lithium Niobate Films With Spurious Suppression

Luis Guillermo Villanueva Torrijo, Soumya Yandrapalli

This work presents the study of suspended Y-cut Lithium Niobate shear bulk acoustic resonators for wide band filter applications in the frequency range of 3.5-4.5GHz. The resonators consist of a Lithium Niobate film with Aluminum top interdigitated electro ...

Institute of Electrical and Electronics Engineers2023

Optimization of elastic wave propagation in a reconfigurable medium by genetic algorithms with adaptive mutation probability

Romain Christophe Rémy Fleury, Janez Rus

We introduce a reconfigurable medium for the manipulation of elastic propagation properties of Lamb waves. It is based on a shape memory polymer (SMP) with temperature-dependent Young's modulus. Waves are excited by a laser pulse and detected by a laser vi ...

IOP Publishing Ltd2023

Fluid flow through microcracked and fractured granitic reservoirs

Marie Estelle Solange Violay, Michael Heap, Lucille Jocelyne Nadine Carbillet

The permeability of crustal rocks and rock-masses dictates the efficiency of hydrothermal circulation and therefore the productivity of geothermal resources. In this study, we find by monitoring P-wave velocity that thermal microcracking in Lanhélin granit ...

2023

Controlling the crystal structure of succinic acid via microfluidic spray-drying

Esther Amstad, Aysu Ceren Okur

Many properties of materials, including their dissolution kinetics, hardness, and optical appearance, depend on their structure. Unfortunately, it is often difficult to control the structure of low molecular weight organic compounds that have a high propen ...

ROYAL SOC CHEMISTRY2023

Nanoindentation of embedded particles

Andreas Mortensen, Alejandra Inés Slagter, Joris Pierre Everaerts

We address the effect of elastic inhomogeneity on elastic modulus and hardness determinations made by depth-sensing indentations performed on individual particles embedded within a matrix of different elastic modulus. Finite element simulations and nanoind ...

SPRINGER HEIDELBERG2023

Dissipative Solitons and Switching Waves in Dispersion-Modulated Kerr Cavities

Tobias Kippenberg, Rui Ning Wang, Johann Emmeram Riemensberger, Miles Henry Anderson, Alexey Tikan, Aleksandr Tusnin, Alisa Davydova

We theoretically and experimentally investigate the formation of dissipative coherent structures in Kerr nonlinear optical microresonators, whose spectrum encompasses an integrated dispersion that exceeds the cavity free-spectral range. We are able to acce ...

American Physical Society2023

cRacklet: a spectral boundary integral method library for interfacial rupture simulation

Jean-François Molinari, Fabian Barras, Thibault Didier Roch

The study of dynamically propagating rupture along interfaces is of prime importance in various fields and system sizes, including tribology (nm to m), engineering (mm to m) and geophysics (m to km) (Armstrong-Hélouvry et al., 1994; Ben-Zion, 2008; Vanossi ...

2022

Transition from sub-Rayleigh anticrack to supershear crack propagation in snow avalanches

Johan Alexandre Philippe Gaume, Bertil Trottet, Grégoire Bobillier

Avalanches can occur when a porous snow layer lies beneath a dense cohesive snow slab. Field experiments and simulations now reveal different crack-propagation regimes in slab avalanches, similar to rupture propagation following an earthquake. ...

NATURE PORTFOLIO2022

Determination of Parameters Characteristic of Dynamic Weakening Mechanisms During Seismic Faulting in Cohesive Rocks

Marie Estelle Solange Violay, François Xavier Thibault Passelègue, Chiara Cornelio

While sliding at seismic slip-rates of ∼1 m/s, natural faults undergo an abrupt decrease of shear stress called dynamic weakening. Asperity-scale processes related to flash heating and weakening and, meso-scale (mm-cm) processes involving shear across the ...

AGU2022

Development of Thin Film Lithium Niobate Shear Bulk Acoustic Wave Resonators

Soumya Yandrapalli

RF MEMS piezoelectric acoustic resonators are the essential building blocks for RF filters used in RF front-end modules for wireless mobile communication due to their compact size in the MHz-GHz frequency range, high Quality factors and large relative band ...

EPFL2022

An Extension of the Guided Wave M‐Component Model Taking Into Account the Presence of a Tall Strike Object

Farhad Rachidi-Haeri, Marcos Rubinstein, Mohammad Azadifar, Quanxin Li

We present in this paper an extension of the guided-wave M-component model of Rakov et al. considering the presence of a vertically elevated strike object. The tall object is represented as a lossless, uniform transmission line. Expressions for the current ...

2021

Origin of the Co‐Seismic Variations of Elastic Properties in the Crust: Insight From the Laboratory

Marie Estelle Solange Violay, François Xavier Thibault Passelègue, Mateo Alejandro Acosta, Federica Paglialunga

Seismological observations highlighted that earthquakes are often followed by changes in elastic properties around the fault zone. Here, we studied the origin of these variations using stick-slip experiments on saw-cut granite samples presenting different ...

2021

Crack propagation speeds in weak snowpack layers

Johan Alexandre Philippe Gaume, Bertil Trottet, Grégoire Bobillier

For the release of a slab avalanche, crack propagation within a weak snowpack layer below a cohesive snow slab is required. As crack speed measurements can give insight into underlying processes, we analysed three crack propagation events that occurred in ...

CAMBRIDGE UNIV PRESS2021

Study on the Performances of AlScN based SAW/BAW Hybrid Resonators A Parametric Analysis of Acoustic Wave Resonators with Large Figure of Merit

Luis Guillermo Villanueva Torrijo, Soumya Yandrapalli

In this study, we analyze a 3rd type of FBAR's fundamental mode by finite element method. We show the importance of the substrate's wave velocity and conductivity on the electromechanical coupling efficiency. Then we demonstrate that etching traditional SA ...

IEEE2021