Publications associées à Electromagnetic wave equation

Maximum Radiation Efficiency of an Implantable Antenna: The Role of High-Order Modes

Anja Skrivervik, Mingxiang Gao, Jakub Liska

A combination of two numerical techniques of computational electromagnetics, namely, method of moments and vector spherical wave expansion, is used to show performance limitations on the radiation efficiency of implantable antennas and to efficiently resol ...

IEEE2023

Multipolar expansions for scattering and optical force calculations beyond the long wavelength approximation

Olivier Martin, Karim Achouri, Andrei Kiselev, Marco Riccardi

We review three different approaches for the calculation of electromagnetic multipoles, namely, the Cartesian primitive multipoles, the Cartesian irreducible multipoles, and the spherical multipoles. We identify the latter as the best suited to describe th ...

AMER PHYSICAL SOC2022

On the reconstruction of the attenuation function of a return-stroke current from the Fourier Transform of finite-duration measurements

Farhad Rachidi-Haeri, Marcos Rubinstein

A correct representation of the lightning current is crucial when the electromagnetic field radiated to a point of interest has to be computed. Based on the engineering models of Transmission Line type, such representation involves the knowledge of the ret ...

2022

Multipolar origin of electromagnetic transverse force resulting from TE/TM wave interference

Olivier Martin, Karim Achouri, Andrei Kiselev

In this paper, we aim at unveiling the underlying physical mechanism for transversal optical forces, appearing due to the simultaneous illumination of a spherical object with two plane waves possessing different polarizations. The appearance of such a tran ...

2021

Magnons, worms and nanogratings in artificial magnetic quasicrystals

Sho Watanabe

Magnons (spin waves, SWs) are elementary spin excitations in magnetically ordered materials. They are the promising quanta for the transmission and processing of information. Magnons can be coupled to the electromagnetic waves utilized for the wireless com ...

EPFL2021

Multipolar origin of electromagnetic transverse force resulting from two-wave interference

Olivier Martin, Karim Achouri, Andrei Kiselev

We propose a theoretical study on the electromagnetic forces resulting from the superposition of TE and TM plane waves interacting with a sphere. Specifically, we first show that, under such an illumination condition, the sphere is subjected to a force tra ...

AMER PHYSICAL SOC2020

Limitations of the Metasurface Diluted-Slab Model

Karim Achouri, Christophe Caloz

In this article, we investigate the possibility to model a metasurface, defined as a zero-thickness sheet of surface polarization currents and described by generalized sheet transition conditions (GSTCs), by a thin slab with a subwavelength thickness and u ...

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC2020

A Study of a Large Bipolar Lightning Event Observed at the Säntis Tower

Farhad Rachidi-Haeri, Marcos Rubinstein, Mohammad Azadifar, Wolfgang Schulz, Davide Pavanello

An unusual negative lightning flash was recorded at the Säntis Tower on June 15, 2012. The flash did not contain an initial continuous current typical of upward negative lightning, which is the most common type of event at the Säntis Tower. The flash conta ...

2019

Tomographic imaging with harmonic holography in tissues of known refractive index distribution

Demetri Psaltis, Ye Pu

High-resolution imaging in thick biological tissues beyond a few transport mean free path of photons remains a formidable challenge to modern science and technology. Recent advancements in optical tomography have enabled the reconstruction of the three-dim ...

SPIE-INT SOC OPTICAL ENGINEERING2018

Design considerations for implantable and wearable antennas

Anja Skrivervik

This contribution gives a review of our results characterizing the propagation in lossy biological tissues. These results were mainly obtained using a simplified spherical model allowing a description in spherical wave decomposition. This model is of cours ...

IEEE2017

Second-harmonic radiating imaging probes and harmonic holography

Demetri Psaltis, Ye Pu, Ye Pu

Compared with other imaging probes such as fluorescent dyes and quantum dots, second-harmonic radiating imaging probes (SHRIMPs) provide a unique ultrafast, coherent optical contrast that is free of photobleaching and emission intermittency. Using the seco ...

Spie-Int Soc Optical Engineering2016

Analysis of photonic crystal defect modes by maximal symmetrization and reduction

Marc-André Dupertuis, Benjamin Gallinet

We analyze in depth the eigenmodes symmetry of the vectorial electromagnetic wave equation with discrete symmetry, using a recently developed maximal symmetrization and reduction scheme leading to an automatic technique which decomposes every mode into its ...

2010

Electromagnetic modelling of planar circuits in bounded layered media

Pedro Crespo Valero

Printed circuits in bounded media encompass a wide range of practical structures such as discontinuities in waveguides, planar circuits embedded in shielded multilayered media or even two-dimensional printed periodic structures. The Electromagnetic (EM) mo ...

EPFL2007

Return stroke current profiles and electromagnetic fields associated with lightning strikes to tall towers: Comparison of engineering models

Farhad Rachidi-Haeri, Davide Pavanello, José-Luis Bermudez

In this paper, we compare five engineering return stroke models, extended to include the presence of an elevated strike object, namely the Bruce-Golde (BG) model, the transmission line (TL) model, the traveling current source (TCS) model, and the two modif ...

2007