Philippe Pernod

École Centrale de Lille | EC Lille · Institute of Electronics Microelectronics and Nanotechnology (IEMN)

Magnetostrictive thin films, exhibit significant utility as functionalization materials for Surface acoustic wave sensors designed for magnetic field measurements. This research investigates the influence of annealing under vacuum and magnetic field at various temperatures on the magnetic properties of the FeCo/TbCo2 thin film and therefore on the...

Surface Acoustic Wave (SAW) sensors represent a prominent technological avenue for quantifying mechanical stress-induced deformations. Nonetheless, the integration of these Micro-Electro-Mechanical Systems (MEMS) sensors remains an complex challenge. Consequently, a common approach within a multitude of research involves the utilization of a adhesi...

New designs based on S0 Lamb modes in AlN thin layer resonating structures coupled with the implementation of structural elements in SiO2, are theoretically analyzed by the Finite Element Method (FEM). This study compares the typical characteristics of different interdigital transducer (IDTs) configurations, involving either a continuous SiO2 cap l...

Surface Acoustic Wave (SAW) sensors represent a prominent technological avenue for quantifying mechanical stress-induced deformations. Nonetheless, the integration of these Micro-Electro-Mechanical Systems (MEMS) sensors remains an complex challenge. Consequently, a common approach within a multitude of research involves the utilization of a adhesi...

As part of the education reform of the École Centrale de Lille, a new lecture for the “ Internet of Things ” has been created. Entitled “ Mobile networks, IoT and UHS (Ultra High Speed) communications ” and taught in English it takes place in the “ Advanced communication networks ” teaching unit (UE) for the third year students of the École Central...

This study focuses on the investigation of RF Lamb acoustic waveguide sensitivity to magnetic field in piezomagnetic composite membrane under an applied magnetic field. RF acoustic wave Device was fabricated on AlN/Diamond membrane enabling the excitation of three modes with different polarisation A0, SH0, and S0 on the same platform. Magnetostrict...

This study proposes the complete design of a dynamic measurement system of mechanical deformation. The final objective concerns the remote monitoring of mechanical stresses in electrical machines in order to address the issues of Industry 4.0 and predictive maintenance. The work carried out in this study concerns the design, fabrication and charact...

We present the fabrication and utilization of a SAW resonator based MEMS gas sensor for the detection of volatile organic compounds (VOCs) traces. The resonator is made of gold electrodes that are sensitive to the chemical composition of the gas. The device was tested in an experimental setup alternating a pure nitrogen flow and a "polluted" nitrog...

Surface acoustic waves (SAWs) have a broad spectrum of applications, especially in sensing. However, deposition methods of sensitive layers can be controlled locally through electrodeposition unlike other conventional methods, such as drop-casting and atmospheric-pressure plasma. Employing this method, we experimentally demonstrate the local electr...

Cette étude propose la conception complète d’un système de suivi à distance des sollicitations mécaniques dans les machines électriques afin de répondre aux problématiques de l’industrie 4.0 et de la maintenance prédictive. Elle s’appuie sur la conception, la fabrication et la caractérisation de MEMS acoustiques hautes fréquences (bande ISM à 433MH...

We propose a simple solid–liquid–solid triple layer biosensor platform based on bound states in the continuum (BICs) and Fano resonances to detect the acoustic properties of liquids and apply the method to a mixture of water and albumin with various concentrations. The solid–liquid–solid triple layer is composed of an epoxy as a solid layer and an...

Electrical control of conjugate degrees of freedom in multiferroics provides the advantage of reducing energy consumption to femto-and even attojoules per switch in spintronics and memory devices. This is achieved through the development of technologies that make it possible to fabricate artificial materials with constantly improving properties. He...

We study experimentally and theoretically the dynamics of spin relaxation motion excited by a femtosecond pulse in the TbCo 2 /FeCo multilayer structures with different ratios of TbCo 2 to FeCo thicknesses r d = d TbCo2 / d FeCo . The main attribute of the structure is in-plane magnetic anisotropy artificially induced during sputtering under DC mag...

Parametric instability of a standing gravity–capillary wave is observed in conditions of irradiation of a surface of a liquid by a plane ultrasound beam modulated by amplitude. A threshold value of ultrasound intensity for excitation of the parametric oscillations of the surface is determined, and the frequency response of the process is measured....

This paper presents and discusses the first demonstration of aerodynamic wall pressure measurement using a thermal Pirani effect based micro-sensor. The thermal micro-sensor is designed as a suspended micro-hot-wire separated from the substrate by a nanoscale gap, and mechanically supported by perpendicular micro-bridges. The micro-sensor was calib...

Phase Change Materials (pcm) have been widely used for thermal energy storage due to their high latent heat of fusion. However, PCMs suffer from their very low thermal conductivity which limits heat spreading around the heat source. Without proper thermal conductivity enhancement, melting would occur mainly around the heat source and heat would be...

Bound states in continuum (BICs) are resonances with zero width (infinite lifetime) without any leakage into the surrounding media. Their fascinating properties and potential applications have attracted a great deal of interest. In this paper, we give an analytical, numerical, and experimental demonstration of BICs in simple acoustic structures bas...

A thermoacoustic sound generation model, based on the classical balance equations of the continuum mechanics, is here developed for the cylindrical and the spherical thermoacoustic wave generation. In both geometries, the model considers an arbitrary multilayered structure, where each layer can be fluid or solid and it is characterized by the fully...

The interaction of the Wave Phase Conjugation (WPC) process with bubble cloud dynamics is investigated via numerical modeling in application to bubble size measurements. The WPC simulator by Modarreszadeh and Timofeev (Computers and Fluids 197, 104353) is used as a starting point. In the simulator, a modified version of the high-order Nodal Discont...

Polarization of electromagnetic waves plays an extremely important role in interaction of radiation with matter. In particular, interaction of polarized waves with ordered matter strongly depends on orientation and symmetry of vibrations of chemical bonds in crystals. In quantum technologies, the polarization of photons is considered as a “degree o...

A simplified method for measurements of low interfacial tension coefficient which is applicable for binary mixtures is proposed. The technique is based on generating progressive capillary waves at a liquid interface by radiation pressure of a short ultrasound pulse in microgravity condition. The waveforms are then processed in the spatial domain. T...

This paper presents and discusses the development of a normally-off magneto-mechanical airflow microvalve designed for active aerodynamic flow control application. The architecture of the microvalve is composed of a highly flexible mechanical resonator, a miniature coil enabling the magnetic resonator actuation and a packaging with oval shape. The...

In this work, the effects of the N2 addition to the SF6 plasma used in the isotropic silicon etching of Micro-electromechanical systems (MEMS) with Au components are investigated. A four-variables Doehlert design was implemented for optimizing the etching parameters (power, pressure, gas flow rate, and N2/SF6 ratio) to maximize the lateral etch rat...

Abstract Intermetallic heterostructures of rare-earth and transition metals exhibit physical properties prospective for various applications. These structures combine giant magnetostriction, controllable magnetic anisotropy, magneto-optical activity and allow spin reorientation transitions (SRT) induced by magnetic field at room temperature. Here,...

In the past decade, a lot of research has been conducted on the potential of carbon nanostructured materials to emit sound via thermoacoustics through both simulations and experiments. However, experimental validation of simulations for three-dimensional graphene (3D-C), which has a complicated 3D structure, has yet to be achieved. In this paper, 3...

Phase Change Materials (PCM) have been widely used for thermal energy storage due to their high latent heat of fusion. However, PCMs suffer from their very low thermal conductivity which limits heat spreading around the heat source. Without proper thermal conductivity enhancement, melting would mainly occur at the interface between the heated surfa...

Acoustic resonators based on antiferromagnetic crystals of “easy plane” type, like a-Fe2O3 or FeBO3, are of interest for applications in magnetoacoustic sensors of electrical and mechanical values because of high sensitivity of their resonance frequency to variations of external magnetic field or mechanical stress. One of requirements for magnetic...

This paper presents and discusses the results obtained with a MEMS (Micro-Electro-Mechanical System) high temperature gradient sensor for time-averaged and fluctuating skin-friction measurements in highly turbulent flows. Designed as a robust wall-mounted suspended hot-wire structure, the micro-sensor was made using conventional microfabrication te...

In this work, we propose a theoretical and experimental investigation of the interaction of guided pure shear-horizontal (SH) wave within a uniaxial multilayered TbCo2/FeCo thin film deposited on ST-X90∘-cut quartz in a delay-line configuration. We evaluate theoretically the evolution of phase velocity as a function of magnetic field and experiment...

The magnetoelectric properties of laminated heterostructures consisting of ferromagnetic yttrium iron garnet (YIG) films deposited on antiferroelectric (AFE) (Pb 0.97 La 0.02 )(Zr 0.6 Sn 0.3 Ti 0.1 )O 3 (PLZST) and on ferroelectric (FE) 0.75Pb(Mg 1/3 Nb 2/3 )O 3 -0.25Pb(Zr 0.48 Ti 0.52 )O 3 (PMN-PZT) ceramics are compared in this work. In particula...

The magnetic moment dynamics excited by 35 fs laser pulses in TbCo2/FeCo heterostructure is experimentally investigated by pump-probe technique. The studies are carried out in two typical geometries with magnetizing field perpendicular and along to easy magnetization axis. In "the easy axis" orientation, high-frequency oscillations of magnetic mome...

Results are presented from an experimental study of the equilibrium distribution of magnetization and processes of magnetization reversal of magnetoelastic nanostructures in the form of strips with constant or variable width. It is shown that the symmetry of the stable magnetization states in the nanostrip can be broken by a static magnetic field a...

Straintronic principle of nonvolatile magnetoelectric random access memory (MELRAM) draws much attention due to the prospects of ultra-low energy consumption in storage devices. The switching of magnetic moments by pulsed deformation of elastically coupled magnetic and piezoelectric subsystems is accompanied by excitation of acoustic oscillations i...

Исследованы магнитные свойства и ферромагнитный резонанс в гетероструктуре, состоящей из эпитаксиальной пленки железо-иттриевого граната (Y 3 Fe 5 O 12 ) и редкоземельной интерметаллической сверхрешетки нанометровой толщины, представляющая собой обменно-связанные слои (TbCo 2 /FeCo) n . Сверхрешетка (TbCo 2 /FeCo) n обеспечивает гигантскую магнитос...

A method dedicated to the measurement of low surface tension coefficients in binary fluids is proposed. The method which is not intrusive and does not interfere with the volume/weight proportion of liquid composing the binary mixture utilizes excitation of progressive capillary waves by pulsed radiation pressure force of focused ultrasound beam. A...

A new type of instability of standing gravity—capillary waves has been detected under the irradiation of the liquid surface by a continuous plane ultrasonic beam with a constant amplitude. At an intensity of 1.03-MHz ultrasound above a certain threshold, the excitation of one of the eigenmodes of gravity—capillary waves at a frequency of 6.56 Hz ha...

Thermoacoustic sound generation offers a promising wideband alternative to mechanically driven loudspeakers. Over the past decade, the development of nanomaterials with new physicochemical properties promoted wide interest in thermophone technology. Indeed, several thermophone structures based on suspended nanowires, graphene sheets, highly porous...

The electric field (E) controlled magnetism in the multiferroic heterostructure comprising polycrystalline yttrium iron garnet (YIG) film, Pt electrodes, and lead magnesium niobate-lead zirconate titanate (PMN-PZT) ceramic is presented in this work. The electric-field-dependent magnetization and susceptibility of YIG film reveal the strain-mediated...

The magnetoelectric properties of a laminated heterostructure consisting of ferromagnetic yttrium iron garnet (YIG) film and antiferroelectric (Pb0.97La0.02) (Zr0.6Sn0.3Ti0.1)O3 (PLZST) ceramic is, for the first time, reported in this work. The electric-field-controlled susceptibility, a shift of the coercive magnetic field and magnetization variat...

A complex study of the electron transport and magnetic characteristics of epitaxial manganite films La0.7Ba0.3MnO3 (LBMO) was carried out under conditions of the crystal structure tension caused by a mismatch between the parameters of the LBMO crystal and the substrate. The epitaxial thin films with the thickness 40–100 nm were grown by pulsed lase...

The magnetic properties of heterostructures consisting of two films are studied. The upper layer involves rare-earth intermetallic nanostructured superlattices consisting of exchange-coupled layers (TbCo2/FeCo)n (TCFC), and the lower layer includes either epitaxial manganite La0.7Sr0.3MnO3 (LSMO) with optimum strontium doping or an epitaxial film o...

The electron transport properties of strained thin La0.7Ba0.3MnO3 (LBMO) epitaxial films are studied. Films 40–100 nm in thickness were prepared by laser ablation at a temperature T = 700–800°C in pure oxygen atmosphere of 0.3–1 mBar. Ferroelectric crystal substrates (011)0.79PbMg1/3Nb2/3O3–0.21-PbTiO3 (PMN–PT) with a Curie temperature of 150°C and...

We investigate highly confined and isolated surface modes in a phononic crystal plate based on pillars with cap layers. The structure is made of a thin membrane supporting periodic pillars each composed of one cylinder surmounted by a disk shaped cap layer. An optimal choice of the geometrical parameters and material composition allows the structur...

Coupling between dynamic strain and magnetization in ferromagnetic thin films has attracted special consideration as it presents both intriguing fundamental physics problems and technological importance for potential multi-functional devices and information handling. The dynamic strain can be generated by acoustic waves including bulk, surface or g...

Nonlinear parametric coupling of gravity-capillary waves (GCW) by ultrasound wave impinging on a liquid surface is studied experimentally. Modulation of the plane wave radiation pressure by dynamically curved surface of the liquid is considered as a mechanism of the coupling. The standing GCW modes are excited near antinodes by ultrasound beam of c...

The possibility of using the magneto-optical Kerr effect in thin magnetostrictive films to study the piezoelectric characteristics of ferroelectrics is demonstrated experimentally and theoretically. A 〈011〉 PMN-PT ferroelectric crystal with an N*(TbCo2/FeCo) magnetostrictive nanostructure deposited on its surface is the object of study.

Autler-Townes splitting (ATS) and electromagnetically induced transparency (EIT) are similar phenomena but distinct in nature. They have been widely discussed and distinguished by employing the Akaike information criterion (AIC). However, such work is lacking in acoustic systems. In this work, the interaction of Love waves with a two-line pillared...

The need to study ultrafast processes in magnetism is due to the prospects for creating ultrafast magnetic recording and ultrafast spintronic devices. In order to excite the magnetic subsystem femtosecond optical pulses are used. The excitement is manifested as in spin precession. In metals, the material is heated first due to significant optical a...

A general model for thermoacoustic sound generation, based on the classical conservation laws of mass, momentum and energy, is presented and adopted to analyze different thermophone structures. This model is able to describe an arbitrary multilayered (or laminated)system composed of both solid and fluid layers. In each layer, we consider the propag...

The interaction of Love waves with square array of pillars deposited on a cavity defined in a 2D holey phononic crystal is numerically investigated using Finite Element Method. First, the existence of SH surface modes is demonstrated separately for phononic crystals that consist of square arrayed holes, or rectangular arrayed Ni pillars, respective...

The Magneto-Optic Kerr Effect (MOKE) technique has been used to investigate the magnetic properties of Ni thin films, with thickness t ranging from 9 to 163 nm, evaporated onto several substrates (glass, Si (111), mica and Cu) with and without an evaporated Cu underlayer. The MOKE observations were correlated with the surface morphology inferred fr...

A microscale low power high temperature gradient calorimetric (HTGC) sensor measuring both mean and fluctuating bidirectional wall shear stress is presented. The micromachined sensor is composed of three free-standing \(3\,\upmu \text {m}\times 1\) mm micro-wires mechanically supported using perpendicular micro-bridges. The static and dynamic chara...