Publications related to Toroidal moment

Shedding light on the MRI-driven dynamo in a stratified shearing box

We study the magneto-rotational instability (MRI) dynamo in a geometrically thin disc (H/R < 1) using stratified zero net (vertical) flux shearing box simulations. We find that mean fields and electromotive forces (EMFs) oscillate with a primary frequency ...

2024

The time-domain Cartesian multipole expansion of electromagnetic fields

Farhad Rachidi-Haeri, Marcos Rubinstein, Elias Per Joachim Le Boudec, Nicolas Mora Parra, Chaouki Kasmi, Emanuela Radici

Time-domain solutions of Maxwell’s equations in homogeneous and isotropic media are paramount to studying transient or broadband phenomena. However, analytical solutions are generally unavailable for practical applications, while numerical solutions are co ...

Nature Publishing Group2024

Pyroelectricity in poled all-organic polar polynorbornene/polydimethylsiloxane-based stretchable electrets

Frank Nüesch, Francis Owusu

Pyroelectricity in a recently developed all-organic composite electret with a polar polynorbornene-based filler and polydimethylsiloxane (PDMS) matrix has been studied with the help of thermal and dielectric techniques. Measurement of the pyroelectric p co ...

Royal Society of Chemistry2024

Magnetism of Single Surface Adsorbed Atoms Studied with Radio-Frequency STM

Clément Marie Soulard

This thesis investigates the magnetic properties of single atoms and molecules adsorbed on thin magnesium oxide decoupling layers, grown on a silver single crystal. To address these systems experimentally, we use a low temperature scanning tunneling micros ...

EPFL2024

Highly Strained Oxygen‐Doped Chiral Molecular Belts of the Zigzag‐Type with Strong Circularly Polarized Luminescence

Jieping Zhu, Shuo Tong

Herein we report a two-directional cyclization strategy for the synthesis of highly strained depth- expanded oxygen-doped chiral molecular belts of the zigzag-type. From the easily accessible resorcin[4]arenes, an unprecedented cyclization cascade generati ...

Wiley-VCH Verlag GmbH2023

Universal machine learning for the response of atomistic systems to external fields

Yaolong Zhang

Machine learned interatomic interaction potentials have enabled efficient and accurate molecular simulations of closed systems. However, external fields, which can greatly change the chemical structure and/or reactivity, have been seldom included in curren ...

Nature Portfolio2023

AC loss and electrical resistance of the RW3 diffusion-bonded joint

Vincenzo D'Auria

For the European DEMO fusion reactor, several options of the Toroidal Field (TF) coil design were proposed. The winding of the TF coil option 1 is based on React&Wind (RW), Nb3Sn, graded conductors in order to optimize the amount of superconductor accordin ...

2023

A diamond spin qubit scanning probe microscope

Dinesh Kevin Mathais Pinto

The properties of a physical system only exist in relation to its environment. This thesis presents the development of a novel spin qubit scanning probe microscope operating over a wide range of environmental conditions. The qubit, which sits at the heart ...

EPFL2023

Electron temperature fluctuation measurements with Correlation Electron Cyclotron Emission in L-mode and I-mode plasmas at ASDEX Upgrade

Pedro Andres Molina Cabrera

The Correlation Electron Cyclotron Emission (CECE) diagnostic at ASDEX Upgrade (AUG) is used to investigate the features of outer core and pedestal (rho(pol) = 0.85-1.0) turbulence across confinement regime transitions. The I-mode confinement regime is a p ...

E D P SCIENCES2023

Magnetic force microscopy contrast formation and field sensitivity

Marcos Penedo Garcia, Johannes Schwenk

The magnetic force microscope (MFM) is an established experimental tool for imaging stray fields with high spatial resolution and sensitivity. The MFM contrast can however contain contributions from the sample topography, variations in the surface Kelvin p ...

2022

Gas-puff induced cold pulse propagation in ADITYA-U tokamak

Harshita Raj, Ankit Kumar, Abhijit Sen, Rohit Kumar

Short bursts (similar to 1 ms) of gas, injecting similar to 10(17)-10(18) molecules of hydrogen and/or deuterium, lead to the observation of cold pulse propagation phenomenon in hydrogen plasmas of the ADITYA-U tokamak. After every injection, a sharp incre ...

IOP Publishing Ltd2021

Extension of Lorentz reciprocity and Poynting theorems for spatially dispersive media with quadrupolar responses

Olivier Martin, Karim Achouri

We provide a self-consistent extension of the Lorentz reciprocity theorem and the Poynting theorem for media possessing electric and magnetic dipolar and quadrupolar responses related to electric and magnetic fields and field gradients thus corresponding t ...

AMER PHYSICAL SOC2021

Multipolar scattering analysis of hybrid metal-dielectric nanostructures

Olivier Martin, Andrei Kiselev, Debdatta Ray

We perform a systematic study showing the evolution of the multipoles along with the spectra for a hybrid metal-dielectric nanoantenna, a Si cylinder and an Ag disk stacked one on top of another, as its dimensions are varied one by one. We broaden our anal ...

2021

Frequency dependence in GW made simple using a multipole approximation

Tommaso Chiarotti, Andrea Ferretti

In the GW approximation, the screened interaction W is a nonlocal and dynamical potential that usually has a complex frequency dependence. A full description of such a dependence is possible but often computationally demanding. For this reason, it is still ...

AMER PHYSICAL SOC2021

Magnetic structures and quadratic magnetoelectric effect in LiNiPO4 beyond 30 T

Ellen Fogh

Neutron diffraction with static and pulsed magnetic fields is used to directly probe the magnetic structures in LiNiPO4 up to 25 T and 42 T, respectively. By combining these results with magnetometry and electric polarization measurements under pulsed fiel ...

AMER PHYSICAL SOC2020

Investigating Scrape-Off Layer transport in alternative divertor geometries on the TCV tokamak

Roberto Maurizio

Thermonuclear fusion is a potentially clean and limitless energy source that can substantially change the current global electricity generation mix, which is highly dependent on limited fossil fuels. This thesis contributes to the development of fusion en ...

EPFL2020

Coordinate parameterisation and spectral method optimisation for Beltrami field solver in stellarator geometry

David Pfefferlé, Aravind Kumar Chandiran, Antoine Baillod, Ajay Kumar

The numerical solution of the stepped pressure equilibrium (Hudson et al 2012 Phys. Plasmas 19 112502) requires a fast and robust solver to obtain the Beltrami field in three-dimensional geometry such as stellarators. The spectral method implemented in the ...

2020

Sensing the Spin of an Individual Ce Adatom

Wolf-Dieter Schneider, Markus Ternes

The magnetic moment of rare earth elements originates from electrons in the partially filled 4f orbitals. Accessing this moment electrically by scanning tunneling spectroscopy is hampered by shielding of outerlying orbitals. Here, we show that we can detec ...

AMER PHYSICAL SOC2020

Predicting molecular dipole moments by combining atomic partial charges and atomic dipoles

Michele Ceriotti, David Mark Wilkins, Max David Veit, Yang Yang

The molecular dipole moment (mu) is a central quantity in chemistry. It is essential in predicting infrared and sum-frequency generation spectra as well as induction and long-range electrostatic interactions. Furthermore, it can be extracted directly-via t ...

AMER INST PHYSICS2020

Macroscopic polarization in the nominally ergodic relaxor state of lead magnesium niobate

Dragan Damjanovic, Lukas Riemer, Yang Li, Kanghyun Chu, Brahim Dkhil

Macroscopic polarity and its dynamic response to external electric fields and temperature in the nominally ergodic relaxor phase of pristine lead magnesium niobate crystals and ceramics, Pb(Mg1/3Nb2/3)O3 (PMN), were investigated. Dynamic pyroelectric measu ...

AIP American Institute of Physics2020