Publications associées à Discrete dipole approximation

Frequency and time domains interactions in nanophotonics

In this thesis, we discuss the problems of scattering and optical manipulation related to nanosystems of different complexities. The multipolar decomposition method is used to represent scattering processes in nanosystems as a series of elementary excitati ...

EPFL2023

A Multiconfigurational Wave Function Implementation of the Frenkel Exciton Model for Molecular Aggregates

Francesco Aquilante

We present an implementation of the Frenkel exciton model into the OpenMolcas program package enabling calculations of collective electronic excited states of molecular aggregates based on a multiconfigurational wave function description of the individual ...

AMER CHEMICAL SOC2023

Finite element method–discrete element method bridging coupling for the modeling of gouge

Jean-François Molinari, Guillaume Anciaux, Antonio Joaquin Garcia Suarez, Manon Eugénie Voisin--Leprince

We discuss the multiscale modeling of a granular material trapped between continuum elastic domains. The amorphous granular region, usually termed “gouge,” is under high confinement pressure, to represent the loading of faults at depth. We model the granul ...

Wiley2023

Numerical characterization and engineering of transport in morphologically complex heterogeneous media

Xiaoyu Dai

A multi-scale numerical methodology for the assessment of radiation and optical characteristics of complex structured soot-contaminated snow layers was investigated first. The methodology accounted for the exact morphology at the various scales and utilize ...

EPFL2021

Fundamental Properties and Classification of Polarization Converting Bianisotropic Metasurfaces

Olivier Martin, Karim Achouri

We provide a detailed discussion on the electromagnetic modeling and classification of polarization converting bianisotropic metasurfaces. To do so, we first present a general approach to compute the scattering response of suchmetasurfaces, which relies on ...

2021

Imaging plasma formation in isolated nanoparticles with ultrafast resonant scattering

Christoph Bostedt, Daniela Rupp, Alessandro Colombo

We have recorded the diffraction patterns from individual xenon clusters irradiated with intense extreme ultraviolet pulses to investigate the influence of light-induced electronic changes on the scattering response. The clusters were irradiated with short ...

2020

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 Computational Comparison Between Isogeometric Analysis and Spectral Element Methods: Accuracy and Spectral Properties

Alfio Quarteroni, Ondine Gabrielle Chanon

In this paper, we carry out a systematic comparison between the theoretical properties of Spectral Element Methods and NURBS-based Isogeometric Analysis in its basic form, that is in the framework of the Galerkin method, for the approximation of the Poisso ...

SPRINGER/PLENUM PUBLISHERS2020

High-fidelity optical diffraction tomography of multiple scattering samples

Demetri Psaltis, Joowon Lim, Elizabeth Elena Antoine, Ahmed Ayoub

We propose an iterative reconstruction scheme for optical diffraction tomography that exploits the split-step nonparaxial (SSNP) method as the forward model in a learning tomography scheme. Compared with the beam propagation method (BPM) previously used in ...

Springer2019

Studying the different coupling regimes for a plasmonic particle in a plasmonic trap

Olivier Martin, Jeonghyeon Kim

Plasmonic antennas improve the stiffness and resolution of optical tweezers by producing a strong near-field. When the antenna traps metallic objects, the optically-resonant object affects the near-field trap, and this interaction should be examined to est ...

2019

SIMPLE code: Optical properties with optimal basis functions

Nicola Marzari, Gianluca Prandini, Paolo Umari

We present SIMPLE, a code developed to calculate optical properties of metallic and insulating extended systems using the optimal basis method originally proposed by E.L. Shirley in 1996. Two different approaches for the evaluation of the complex dielectri ...

ELSEVIER SCIENCE BV2019

High-resolution interference microscopy with spectral resolution for the characterization of individual particles and self-assembled meta-atoms

Toralf Scharf, Michail Symeonidis, Andreas Vetter

We apply a high-resolution interference microscope with spectral resolution to investigate the scattering response of isolated meta-atoms in real space. The final meta-atoms consist of core-shell clusters that are fabricated using a bottom-up approach. The ...

2019

Optical characterization of multi-scale morphologically complex heterogeneous media – Application to snow with soot impurities

Sophia Haussener, Xiaoyu Dai

A multi-scale methodology for the radiative transfer analysis of heterogeneous media composed of morphologically-complex components on two distinct scales is presented. The methodology incorporates the exact morphology at the various scales and utilizes vo ...

Elsevier2018

Cyanine platelet single crystals: growth, crystal structure and optical spectra

Frank Nüesch, Jakob Heier, Antonia Neels

Crystalline organic semiconducting materials are much in demand for multiple electronic and optoelectronic device applications. Here, solution grown ultrathin rhombic crystals of a trimethine carbocyanine anionic dye are used to establish relationships bet ...

Royal Society of Chemistry2018

Full Discrete Modeling, Controller Design, and Sensitivity Analysis for High-Performance Grid-Forming Converters in Islanded Microgrids

Francisco Daniel Freijedo Fernández, Federico De Bosio

Recent works have shown that the state-feedback decoupling of capacitor voltage allows for drastic bandwidth enlarging of current controllers for grid-forming converters in islanded microgrids. Furthermore, Smith predictor and lead compensation have been a ...

2018

An arbitrary wavelength solver for global gyrokinetic simulations. Application to the study of fine radial structures on microturbulence due to non-adiabatic passing electron dynamics

Laurent Villard, Stephan Brunner, Trach-Minh Tran, Ben McMillan, Gabriele Merlo, Julien Stanislas Pierre Dominski

The influence of the fine layers of the non-adiabatic passing electron response on electrostatic turbulent transport, previously studied systematically in flux tube geometry [Dominski et al., Phys. Plasmas 22, 062303 (2015)], is pursued in global geometry ...

Amer Inst Physics2017

Exact finite volume particle method with spherical-support kernels

François Avellan, Ebrahim Jahanbakhsh, Audrey Paulette Solange Maertens, Christian Vessaz

The Finite Volume Particle Method (FVPM) is a meshless method for simulating fluid flows which includes many of the desirable features of mesh-based finite volume methods. In this paper, we develop a new 3-D FVPM formulation that features spherical kernel ...

Elsevier2017

van der Waals Bonded Co/h-BN Contacts to Ultrathin Black Phosphorus Devices

Ahmet Avsar, Xin Luo

Because of the chemical inertness of two dimensional (2D) hexagonal-boron nitride (h-BN), few atomic-layer hBN is often used to encapsulate air-sensitive 2D crystals such as black phosphorus (BP). However, the effects of h-BN on Schottky barrier height, do ...

Amer Chemical Soc2017

Padé approximation of the adiabatic electron contribution to the gyrokinetic quasi-neutrality equation in the ORB5 code

Laurent Villard, Stephan Brunner, Emmanuel Lanti, Ben McMillan, Julien Stanislas Pierre Dominski

This work aims at completing the implementation of a solver for the quasineutrality equation using a PadÃ© approximation in the global gyrokinetic code ORB5. Initially [Dominski, Ph.D. thesis, 2016], the Pade approximation was only implemented for the kine ...

2016

Riemannian Optimization For High-Dimensional Tensor Completion

Michael Maximilian Steinlechner

Tensor completion aims to reconstruct a high-dimensional data set where the vast majority of entries is missing. The assumption of low-rank structure in the underlying original data allows us to cast the completion problem into an optimization problem rest ...

Siam Publications2016