Publications by Ellen Fogh | EPFL Graph Search

Demagnetization factors and field of hemispherical objects

Demagnetization factors play an important role in micromagnetics modeling but exact solutions only exist for a limited number of particle shapes. Here we use a Fourier space based approach coupled to the concept of magnetic charges to derive analytically t ...

2025

Confined and Deconfined Spinon Excitations in the Rectangular-lattice Quantum Antiferromagnet

Henrik Moodysson Rønnow, Bruce Normand, Ellen Fogh, Noore Elahi Shaik

Fractionalization remains one of the most fascinating manifestations of strong interactions in quantum many-body systems. In quantum magnetism, the existence of spinons-collective magnetic excitations that behave as quasiparticles with fractional quantum n ...

AMER PHYSICAL SOC2025

Bullet pressure-cell design for neutron scattering experiments with horizontal magnetic fields and dilution temperatures

Henrik Moodysson Rønnow, Richard Gaal, Luc Testa, Ellen Fogh, Gaétan Charles Antoine Giriat, Jana Pásztorová

The simultaneous application of high magnetic fields and high pressures for controlling magnetic ground states is important for testing our understanding of many-body quantum theory. However, the implementation for neutron scattering experiments presents a ...

2025

Cooper Pairs of Bosons in a Quantum Magnet Revealed by Neutron Spectroscopy Under Very High Magnetic Fields

Ellen Fogh

2024

Magnon interactions in a moderately correlated Mott insulator

Henrik Moodysson Rønnow, Ellen Fogh, Noore Elahi Shaik

Quantum fluctuations in low-dimensional systems and near quantum phase transitions have significant influences on material properties. Yet, it is difficult to experimentally gauge the strength and importance of quantum fluctuations. Here we provide a reson ...

Nature Research2024

Magnetic structure and magnetoelectric properties of the spin-flop phase in LiFePO4

Ellen Fogh, Sofie Janas, Paola Caterina Forino

We investigate the magnetic structure and magnetoelectric(ME) effect in the high -field phase of the antiferromagnet LiFePO 4 above the critical field of 31 T. A neutron diffraction study in pulsed magnetic fields reveals the propagation vector to be q = 0 ...

Amer Physical Soc2024

Field-induced bound-state condensation and spin-nematic phase in SrCu2(BO3)2 revealed by neutron scattering up to 25.9 T

Henrik Moodysson Rønnow, Frédéric Mila, Bruce Normand, Ellen Fogh, Jian Rui Soh, Mithilesh Nayak, Alexandra Angeline Turrini

In quantum magnetic materials, ordered phases induced by an applied magnetic field can be described as the Bose-Einstein condensation (BEC) of magnon excitations. In the strongly frustrated system SrCu2(BO3)(2), no clear magnon BEC could be observed, point ...

Nature Portfolio2024

Spin Waves and Three Dimensionality in the High-Pressure Antiferromagnetic Phase of SrCu2 (BO3)2

Henrik Moodysson Rønnow, Frédéric Mila, Bruce Normand, Ellen Fogh, Jian Rui Soh, Gaétan Charles Antoine Giriat

Quantum magnetic materials can provide explicit realizations of paradigm models in quantum many-body physics. In this context, SrCu2(BO3)2 is a faithful realization of the Shastry-Sutherland model for ideally frustrated spin dimers, even displaying several ...

2024

Electrical and Magnetic Properties of FeGa3 with Antisite Disorder

Henrik Moodysson Rønnow, Ivica Zivkovic, Ellen Fogh

We investigated the electronic and magnetic ground states of the cage compound FeGa3 under the presence of Fe antisite disorder (namely as Fe0.258Ga0.742) by x-ray diffraction (XRD), Mössbauer spectroscopy (MS), magnetization and electrical resistivity. Ou ...

2023

The magnetoelectric effect in LiFePO4 - Revisited (vol 648, 414380, 2022)

Henrik Moodysson Rønnow, Ellen Fogh, Alexandre Pages

ELSEVIER2023