Publications related to Eigenmode expansion

The application of the finite-difference time-domain (FDTD) technique to lightning studies

Farhad Rachidi-Haeri, Marcos Rubinstein, Dongshuai Li

We have seen in this chapter that the FDTD method for solving Maxwell's equations is accurate and versatile in a very wide variety of applications related to lightning. One can analyze the lightning electromagnetic field propagation over distances ranging ...

IET2022

Near-Field Mapping of Photonic Eigenmodes in Patterned Silicon Nanocavities by Electron Energy-Loss Spectroscopy

Duncan Thomas Lindsay Alexander, Valentin Flauraud

Recently, there has been significant interest in using dielectric nanocavities for the controlled scattering of light, owing to the diverse electromagnetic modes that they support. For plasmonic systems, electron energy-loss spectroscopy (EELS) is now an e ...

2021

Evaluation of Site Errors in LLS Magnetic Direction Finding Caused by Large Hills Using the 3D‐FDTD Technique

Farhad Rachidi-Haeri, Wolfgang Schulz, Hannes Kohlmann

Angle and amplitude estimation errors in magnetic direction finding, called site errors, are important sensor-specific errors in lightning location systems (LLS). They are known to be caused by nearby cables and overhead lines due to induced currents. Due ...

2021

An Efficient FDTD Method to Calculate Lightning Electromagnetic Fields Over Irregular Terrain Adopting the Moving Computational Domain Technique

Marcos Rubinstein, Mohammad Azadifar, Farhad Rachidi-Haeri, Wenhao Hou, Qilin Zhang

We present an improved finite-difference time domain (FDTD) method based on the moving computational domain technique for the calculation of lightning-generated fields over large-scale irregular terrain. In the improved method, a spatial window moving alon ...

2020

Low-dimensional firing-rate dynamics for populations of renewal-type spiking neurons

Tilo Schwalger

The macroscopic dynamics of large populations of neurons can be mathematically analyzed using low-dimensional firing-rate or neural-mass models. However, these models fail to capture spike synchronization effects and nonstationary responses of the populati ...

AMER PHYSICAL SOC2020

FDTD Modeling of Lightning Electromagnetic Field Propagation Over Mountainous Terrain

Marcos Rubinstein, Dongshuai Li

The Full-Wave Finite-Difference-Time-Domain (FDTD) electromagnetic (EM) simulation method can simulate large domains and produce time-marching solutions for arbitrary time-domain sources, making it ideal for many lightning applications. In this paper, a tw ...

IEEE2019

Dot pattern generation using thick sinusoidal phase grating under Gaussian beam illumination

Toralf Scharf, Maryam Yousefi

Far-field dot pattern generation is analyzed for a Gaussian beam source that illuminates a sinusoidal phase grating which is placed at a certain distance behind the beam waist. We obtain a bigger field of view with more numbers of points using a Gaussian b ...

SPIE-INT SOC OPTICAL ENGINEERING2019

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

Investigation of the Propagation Length of Bloch Surface Waves on One Dimensional Photonic Crystals

Hans Peter Herzig, Nicolas Maxime André Descharmes, Gaël David Osowiecki, Babak Vosoughi Lahijani

A 1D photonic crystal structure sustaining optical surface waves is investigated. The propagation length of the surface mode is studied both using an eigenmode model and a rigorous time domain solver. The two models show good convergence. Our results demon ...

IEEE2018

Learning Tomography Assessed Using Mie Theory

Michaël Unser, Demetri Psaltis, Joowon Lim

In optical diffraction tomography, the multiply scattered field is a nonlinear function of the refractive index (RI) of the object. The Rytov method relies on a single-scattering propagation model and is commonly used to reconstruct images. Recently, a rec ...

American Physical Society (APS)2018

Disorder effects on the coupling strength of coupled photonic crystal slab cavities

Vincenzo Savona, Juan Pablo Vasco Cano

We study the effects of disorder on the coupling strength of coupled photonic crystal slab cavities by considering fully-3D electromagnetic calculations. Specifically, we investigate two coupled L3 cavities at 30 degrees and 60 degrees configurations, wher ...

2018

A Technique for Calculating Voltages Induced on Twisted-Wire Pairs Using the FDTD Method

Farhad Rachidi-Haeri, Marcos Rubinstein, Akiyoshi Tatematsu

Disturbances in low-voltage control circuits in substations and power plants occur due to lightning or switching surges. Adequate protection of electronic devices in low-voltage control circuits requires the capacity to predict surge phenomena and to evalu ...

Institute of Electrical and Electronics Engineers2017

Analysis of lightning electromagnetic field propagation in mountainous terrain and its effects on ToA-based lightning location systems

Marcos Rubinstein, Mohammad Azadifar, Farhad Rachidi-Haeri, Zhaoyang Wang, Keyhan Sheshyekani, Dongshuai Li, Qilin Zhang

In this paper, we analyze the propagation effects on lightning-radiated electromagnetic fields over mountainous terrain by using a three-dimensional (3-D) finite difference time domain (FDTD) method. We also discuss the time delay error in the time-of-arri ...

Amer Geophysical Union2016

Novel linear analysis for a gyrotron oscillator based on a spectral approach

Stefano Alberti, Minh Quang Tran, Jean-Philippe Hogge, Jérémy Genoud, Trach-Minh Tran

With the aim of gaining a better physical insight into linear regimes in gyrotrons, a new linear model was developed. This model is based on a spectral approach for solving the self-consistent system of equations describing the wave-particle interaction in ...

American Institute of Physics (AIP)2016

Performance estimation for indoor wireless systems using FDTD method

Andrew Charles Mallory Austin

A three-dimensional implementation of the finite-difference time-domain method is used to estimate the down-link outage probability of a direct-sequence code division multiple access system operating in a multi-storey office building in the presence of co- ...

Inst Engineering Technology-Iet2015

On the Development and Evaluation of Spatial-Domain Green's Functions for Multilayered Structures With Conductive Sheets

Juan Ramon Mosig, Michael Mattes, Ioannis Koufogiannis

This work focuses on Green's functions (GFs) of planar multilayered structures that may include an arbitrary number of conductive sheets. The spectral-domain GFs are derived through an automatized strategy based on the propagator matrix technique, while th ...

Institute of Electrical and Electronics Engineers2015

Forced response analysis of hydroelectric systems

François Avellan, Pedro Camilo de Oliveira e Silva, Christophe Nicolet, Philippe Allenbach, Basile Kawkabani, Sébastien Alligné, Antoine Béguin

At off-design operating points, Francis turbines develop cavitation vortex rope in the draft tube which may interact with the hydraulic system. Risk resonance assessment by means of eigenmodes computation of the system is usually performed. However, the sy ...

International Association For Hydraulic Research2014

On the development and evaluation of spatial domain Green Functions for multilayered structures with conductive sheets

Juan Ramon Mosig, Michael Mattes, Ioannis Koufogiannis

This work focuses on Green Functions (GFs) of planar multilayered structures that may include arbitrary number of conductive sheets. The spectral domain GFs are derived through an automatized strategy based on the propagator matrix technique, while the spa ...

2014

An alternate point-wise scheme for Electric Field Integral Equations

Juan Ramon Mosig, Gabriele Rosati

A point-wise approach that can be used efficiently in the numerical solution of Electric Field Integral Equations is introduced. The algorithm is based on the so-called magic distance concept, which defines exactly the point-to-point equivalent of a four-d ...

Wiley-Blackwell2013

On the Validity of Approximate Formulas for the Evaluation of the Lightning Electromagnetic Fields in the Presence of a Lossy Ground

Farhad Rachidi-Haeri

The accuracy of approximate formulas for the evaluation of lightning electromagnetic fields above and inside a lossy ground is investigated taking as reference full-wave numerical results obtained using a parallel implementation of the finite-difference ti ...

Ieee-Inst Electrical Electronics Engineers Inc2013