Publications associées à Magnetic Skyrmions and Skyrmion Clusters in the Helical Phase of Cu2OSeO3

Experimental observation of topological transition in linear and nonlinear parametric oscillators

Romain Christophe Rémy Fleury, Benjamin Apffel

Parametric oscillators are examples of externally driven systems that can exhibit two stable states with opposite phase depending on the initial conditions. In this work, we propose to study what happens when the external forcing is perturbed by a continuo ...

2024

Topological photonic transport in disordered scattering networks

Zhechen Zhang

This Ph.D. thesis unveils the unique topological phenomena occurring in such networks, focusing on the intricate interplay between their Floquet topology, the presence of disorder, and their unitary scattering at microscopic and macroscopic scales. Using t ...

EPFL2024

Anomalous and Chern topological waves in hyperbolic networks

Romain Christophe Rémy Fleury, Aleksi Antoine Bossart, Haoye Qin, Zhechen Zhang

Hyperbolic lattices are a new type of synthetic materials based on regular tessellations in non-Euclidean spaces with constant negative curvature. While so far, there has been several theoretical investigations of hyperbolic topological media, experimental ...

Nature Research2024

Anomalous‐Chern Steering of Topological Nonreciprocal Guided Waves

Romain Christophe Rémy Fleury, Haoye Qin, Qiaolu Chen, Zhechen Zhang

Nonreciprocal topological edge states based on external magnetic bias have been regarded as the last resort for genuine unidirectional wave transport, showing superior robustness over topological states with preserved time-reversal symmetry. However, fast ...

Wiley2024

Hydrodynamical simulations of merging galaxy clusters: giant dark matter particle colliders, powered by gravity

Richard Massey, David Richard Harvey

Terrestrial particle accelerators collide charged particles, then watch the trajectory of outgoing debris - but they cannot manipulate dark matter. Fortunately, dark matter is the main component of galaxy clusters, which are continuously pulled together by ...

Oxford Univ Press2024

High-throughput screening of Weyl semimetals

Nicola Marzari, Davide Campi, Davide Grassano

Topological Weyl semimetals represent a novel class of nontrivial materials, where band crossings with linear dispersions take place at generic momenta across reciprocal space. These crossings give rise to low -energy properties akin to those of Weyl fermi ...

Amer Physical Soc2024

Electron-beam based nanoscale quantum controls

Hoda Shirzad

Advancing quantum technologies depends on the precise control of individual quantum systems, the so-called qubits, and the exploitation of their quantum properties. Nowadays, expanding the number of qubits to be entangled is at the core of the developments ...

EPFL2024

Structural study of nickelate based heterostructures

Jean-Marc Triscone, Duncan Thomas Lindsay Alexander, Bernat Mundet, Chih-Ying Hsu

Heterostructures consisting of SmNiO3 and NdNiO3 alternating layers with additional LaAlO3 spacer layers were grown and fully characterized by means of x-ray diffraction, atomic force microscopy, and scanning transmission electron microscopy. A change in t ...

Aip Publishing2024

Ultrafast control of emergent quantum matter probed by electron microscopy

Benoît Guilhem Michel Binh Truc

In the quest for controlling materials' properties, light as an external stimulus has a special place as it can create new states of matter and enable their ultrafast manipulation. In particular, spintronics, an exciting emergent field relying on the elect ...

EPFL2023

Seeding and Emergence of Composite Skyrmions in a van der Waals Magnet

Klaus Kern, Marko Burghard, Lukas Powalla

Topological charge plays a significant role in a range of physical systems. In particular, observations of real-space topological objects in magnetic materials have been largely limited to skyrmions - states with a unitary topological charge. Recently, mor ...

Wiley-V C H Verlag Gmbh2023

Unconventional Flat Chern Bands and 2e Charges in Skyrmionic Moire Superlattices

Oleg Yazyev, Yifei Guan

The interplay of topological characteristics in real space and reciprocal space can lead to the emergence of unconventional topological phases. In this Letter, we implement a novel mechanism for generating higher-Chern flat bands on the basis of twisted bi ...

AMER CHEMICAL SOC2023

Phase of Topological Lattice with Leaky Guided Mode Resonance

Kirsten Emilie Moselund, Chang Won Lee

Topological nature in different areas of physics and electronics has often been characterized and controlled through topological invariants depending on the global properties of the material. The validity of bulk-edge correspondence and symmetry-related to ...

MDPI2023

Dissipative boundary state preparation

We devise a generic and experimentally accessible recipe to prepare boundary states of topological or non topological quantum systems through an interplay between coherent Hamiltonian dynamics and local dissipation. Intuitively, our recipe harnesses the sp ...

Amer Physical Soc2023

Anomalous topological waves in strongly amorphous scattering networks

Romain Christophe Rémy Fleury, Pierre Delplace, Zhechen Zhang

Topological insulators are crystalline materials that have revolutionized our ability to control wave transport. They provide us with unidirectional channels that are immune to obstacles, defects, or local disorder and can even survive some random deformat ...

2023

Topological Effects in Carbon-based Two-dimensional Nanostructures

Yifei Guan

Recent advances on low-dimensional and topological materials has greatly inspired the research in condensed matter physics. This thesis is devoted to the computational and theoretical study of topological effects in two-dimensional materials, especially na ...

EPFL2023

Complementary screening for quantum spin Hall insulators in two-dimensional exfoliable materials

Nicola Marzari, Antimo Marrazzo, Davide Campi, Davide Grassano

Quantum spin Hall insulators are a class of topological materials that has been extensively studied during the past decade. One of their distinctive features is the presence of a finite band gap in the bulk and gapless, topologically protected edge states ...

Amer Physical Soc2023

Active Acoustic Su-Schrieffer-Heeger-Like Metamaterial

Hervé Lissek, Romain Christophe Rémy Fleury, Mathieu François Padlewski, Maxime Volery, Xinxin Guo

An acoustic dimer composed of two electronically controlled electroacoustic resonators is presented with the view of exploring one-dimensional topological phenomena. Active control allows real-time manipulation of the metamaterial’s properties, including i ...

American Physical Society (APS)2023

Mechanistic study on the evolution of vacancies in graphene by oxidation by scanning tunneling microscopy

Shaoxian Li

Nanostructured graphitic materials, including graphene hosting Å to nanometer-sized pores, have attracted attention for various applications such as separations, sensors, and energy storage. Graphene with Å-scale pores is a promising next-generation materi ...

EPFL2023

Trapping Layers Prevent Dopant Segregation and Enable Remote Doping of Templated Self-Assembled InGaAs Nanowires

Anna Fontcuberta i Morral, Nicholas Paul Morgan, Didem Dede, Valerio Piazza

Selective area epitaxy is a promising approach to definenanowirenetworks for topological quantum computing. However, it is challengingto concurrently engineer nanowire morphology, for carrier confinement,and precision doping, to tune carrier density. We re ...

AMER CHEMICAL SOC2023

Self-Assembly of N-Rich Triimidazoles on Ag(111): Mixing the Pleasures and Pains of Epitaxy and Strain

Ulrich Aschauer, Christian Wäckerlin, Xing Wang, Mehdi Heydari

In the present report, homochiral hydrogen-bonded assemblies of heavily N-doped (C9H6N6) heterocyclic triimidazole (TT) molecules on an Ag(111) substrate were investigated using scanning tunneling microscopy (STM) and low energy electron diffraction (LEED) ...

Amer Chemical Soc2023