Publications associées à Controlling the Quantum Spin Hall Edge States in Two-Dimensional Transition Metal Dichalcogenides

Realization of an atomic quantum Hall system in four dimensions

Modern condensed matter physics relies on the concept of topology to classify matter, from quantum Hall systems to topological insulators. Engineered systems, benefiting from synthetic dimensions, can potentially give access to topological states predicted ...

American Association for the Advancement of Science2024

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

Disclination states in nonreciprocal topological networks

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

Recently, nonreciprocal two-dimensional unitary scattering networks have gained considerable interest due to the possibility of obtaining robust edge wave propagation in their anomalous topological insulating phase. However, zero-dimensional states in such ...

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

Exciton migration in two-dimensional materials

Excitons play an essential role in the optical response of two-dimensional materials. These are bound states showing up in the band gaps of many-body systems and are conceived as quasiparticles formed by an electron and a hole. By performing real-time simu ...

Nature Portfolio2024

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

Magneto-Thermoelectric Transport in Graphene Quantum Dot with Strong Correlations

Oleksandr Kriuchkov

Disorder at etched edges of graphene quantum dots (GQD) enables random all-to-all interactions between localized charges in partially filled Landau levels, providing a potential platform to realize the Sachdev-Ye-Kitaev (SYK) model. We use quantum Hall edg ...

2024

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

Weyl metallic state induced by helical magnetic order

Henrik Moodysson Rønnow, Ivica Zivkovic, Jan Hugo Dil, Jian Rui Soh, Xupeng Yang

In the rapidly expanding field of topological materials there is growing interest in systems whose topological electronic band features can be induced or controlled by magnetism. Magnetic Weyl semimetals, which contain linear band crossings near the Fermi ...

Nature Portfolio2024

Spin-Reorientation-Driven Linear Magnetoelectric Effect in Topological Antiferromagnet Cu3TeO6

Helmuth Berger

The search for new materials for energy -efficient electronic devices has gained unprecedented importance. Among the various classes of magnetic materials driving this search are antiferromagnets, magnetoelectrics, and systems with topological spin excitat ...

Amer Physical Soc2024

Realization of Organocerium-Based Fullerene Molecular Materials Showing Mott Insulator-Type Behavior

Xiaoyu Wang, Pragati Pandey

Electron-rich organocerium complexes (C5Me4H)(3)Ce and [(C5Me5)(2)Ce(ortho-oxa)], with redox potentials E-1/2 = -0.82 V and E-1/2 = -0.86 V versus Fc/Fc(+), respectively, were reacted with fullerene (C-60) in different stoichiometries to obtain molecular m ...

Amer Chemical Soc2024

High-Quality Data Enabling Universality of Band Gap Descriptor and Discovery of Photovoltaic Perovskites

Alfredo Pasquarello, Wei Chen, Haiyuan Wang

Extensive machine-learning-assisted research has been dedicated to predicting band gaps for perovskites, driven by their immense potential in photovoltaics. Yet, the effectiveness is often hampered by the lack of high-quality band gap data sets, particular ...

Amer Chemical Soc2024

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

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

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

Magnon-phonon interactions enhance the gap at the Dirac point in the spin-wave spectra of CrI3 two-dimensional magnets

Iurii Timrov

Recent neutron-diffraction experiments in honeycomb CrI3 quasi-2D ferromagnets have evinced the existence of a gap at the Dirac point in their spin-wave spectra. The existence of this gap has been attributed to strong in-plane Dzyaloshinskii-Moriya or Kita ...

2023

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

Murunskite - a new class of functional material

Davor Tolj

The subject of the present work is discovery and in-depth characterization of a new class of functional materials. Tuning of the bond polarity and orbital occupation with a goal of establishing balance between localization and delocalization of electrons - ...

EPFL2023

Possible restoration of particle-hole symmetry in the 5/2-quantized Hall state at small magnetic field

Frédéric Mila, Loïc Jean Pierre Herviou

Motivated by the experimental observation of a quantized 5/2 thermal conductance at filling nu = 5/2, a result incompatible with both the Pfaffian and the anti-Pfaffian states, we have pushed the expansion of the effective Hamiltonian of the 5/2-quantized ...

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