Publications by Quansheng Wu | EPFL Graph Search

Reply to: Low-frequency quantum oscillations in LaRhIn5: Dirac point or nodal line?

Oleg Yazyev, Quansheng Wu, Amelia Emily-Kay Estry, Shengnan Zhang, Philip Johannes Walter Moll, Matthias Carsten Putzke, Chunyu Guo

Nature Portfolio2023

Giant Chern number of a Weyl nodal surface without upper limit

Oleg Yazyev, Quansheng Wu, Shengnan Zhang

Weyl nodes can be classified into zero-dimensional (0D) Weyl points, 1D Weyl nodal lines, and 2D Weyl nodal surfaces (WNS), which possess finite Chern numbers. Up to date, the largest Chern number of WPs identified in Weyl semimetals is 4, which is thought ...

AMER PHYSICAL SOC2022

Phase transition of layer-stacked borophene under pressure

Oleg Yazyev, Quansheng Wu, Xiao Dong

The 8-Pmmn borophene, a boron analog of graphene, hosts tilted and anisotropic massless Dirac fermion quasiparticles owing to the presence of a distorted graphenelike sublattice. First-principles calculations show that stacked 8-Pmmn borophene is transform ...

AMER PHYSICAL SOC2022

Transport signatures of temperature-induced chemical potential shift and Lifshitz transition in layered type-II Weyl semimetal TaIrTe4

Oleg Yazyev, Quansheng Wu, Meng Yang

Temperature-induced Lifshitz transitions have been identified in several materials. Their chemical potential shows a substantial shift with changing temperature. The common feature of these materials is the coexistence of electron and hole pockets in the v ...

IOP PUBLISHING LTD2021

Temperature dependence of quantum oscillations from non-parabolic dispersions

Oleg Yazyev, Quansheng Wu, Amelia Emily-Kay Estry, Shengnan Zhang, Matthias Carsten Putzke, Chunyu Guo

A versatile methodology to detect topological quasiparticles by transport measurements remains an open problem. Here, the authors propose and experimentally observe the temperature dependence of the quantum oscillation frequency as a signature of non-trivi ...

Nature Portfolio2021

Extremely large magnetoresistance in the "ordinary" metal ReO3

Oleg Yazyev, Quansheng Wu, Shengnan Zhang, Huancheng Chen

The extremely large magnetoresistance (XMR) observed in many topologically nontrivial and trivial semimetals has attracted much attention in relation to its underlying physical mechanism. In this paper, by combining the band structure and Fermi surface (FS ...

AMER PHYSICAL SOC2021

Origin of large magnetoresistance in the topological nonsymmorphic semimetal TaSe3

Jean-Philippe Ansermet, Helmuth Berger, Oleg Yazyev, Alberto Crepaldi, Gabriel Albert Autes, Gianmarco Gatti, Daniel Gosalbez Martinez, Quansheng Wu, Michele Puppin, Shengnan Zhang

TaSe3 is a layered van der Waals semimetal with several inverted band gaps throughout the entire Brillouin zone and nontrivial Z(2) topological indices, which place it at the boundary between a strong and a weak topological phase. Our transport experiments ...

2021

Observation of a singular Weyl point surrounded by charged nodal walls in PtGa

Oleg Yazyev, Jan Hugo Dil, Quansheng Wu, Shengnan Zhang

Constrained by the Nielsen-Ninomiya no-go theorem, in all so-far experimentally determined Weyl semimetals (WSMs) the Weyl points (WPs) always appear in pairs in the momentum space with no exception. As a consequence, Fermi arcs occur on surfaces which con ...

Nature Research2021

Landau Levels as a Probe for Band Topology in Graphene Moire Superlattices

Oleg Yazyev, Quansheng Wu, Yifei Guan

We propose Landau levels as a probe for the topological character of electronic bands in two-dimensional moire superlattices. We consider two configurations of twisted double bilayer graphene (TDBG) that have very similar band structures, but show differen ...

AMER PHYSICAL SOC2021

Unidirectional Kondo scattering in layered NbS2

Helmuth Berger, László Forró, Oleg Yazyev, Christoph Koch, Edoardo Martino, Quansheng Wu, Shengnan Zhang, Philip Johannes Walter Moll, Matthias Carsten Putzke, Konstantin Semeniuk

Crystalline defects can modify quantum interactions in solids, causing unintuitive, even favourable, properties such as quantum Hall effect or superconducting vortex pinning. Here we present another example of this notion-an unexpected unidirectional Kondo ...

NATURE PORTFOLIO2021

Irvsp: To obtain irreducible representations of electronic states in the VASP

Quansheng Wu, Ziyi Wang

We present an open-source program irvsp, to compute irreducible representations of electronic states for all 230 space groups with an interface to the Vienna ab-initio Simulation Package. This code is fed with plane-wave-based wavefunctions (e.g. WAVECAR) ...

ELSEVIER2021

Crystal Field Effect and Electric Field Screening in Multilayer Graphene with and without Twist

Oleg Yazyev, Quansheng Wu

We address the intrinsic polarization and screening of an external electric field in a broad range of ordered and twisted configurations of multilayer graphene, using an ab initio approach combining density functional theory and the Wannier function formal ...

AMER CHEMICAL SOC2021

Moire Flat Bands in Twisted Double Bilayer Graphene

Oleg Yazyev, Quansheng Wu, Fatemeh Haddadi

We investigate twisted double bilayer graphene (TDBG), a four-layer system composed of two AB-stacked graphene bilayers rotated with respect to each other by a small angle. Our ab initio band structure calculations reveal a considerable energy gap at the c ...

AMER CHEMICAL SOC2020

The 2021 quantum materials roadmap

Oleg Yazyev, Quansheng Wu

In recent years, the notion of 'Quantum Materials' has emerged as a powerful unifying concept across diverse fields of science and engineering, from condensed-matter and coldatom physics to materials science and quantum computing. Beyond traditional quantu ...

IOP PUBLISHING LTD2020

Large magnetoresistance and nonzero Berry phase in the nodal-line semimetal MoO2

Oleg Yazyev, Quansheng Wu, Shengnan Zhang, Huancheng Chen

We performed calculations of the electronic band structure and the Fermi surface as well as measured the longitudinal resistivity rho(xx)(T,H), Hall resistivity rho(xy)(T,H), and quantum oscillations of the magnetization as a function of temperature at var ...

2020

Correlated states in twisted double bilayer graphene

Oleg Yazyev, Na Li, Quansheng Wu, Jian Tang, Rong Yang, Cheng Shen

Electron-electron interactions play an important role in graphene and related systems and can induce exotic quantum states, especially in a stacked bilayer with a small twist angle(1-7). For bilayer graphene where the two layers are twisted by the 'magic a ...

NATURE PUBLISHING GROUP2020

Non-Abelian reciprocal braiding of Weyl points and its manifestation in ZrTe

Oleg Yazyev, Quansheng Wu

Weyl points in three-dimensional systems with certain symmetry carry non-Abelian topological charges, which can be transformed via non-trivial phase factors that arise upon braiding these points inside the reciprocal space. ...

NATURE PUBLISHING GROUP2020

Artificial Neural Network Approach to the Analytic Continuation Problem

Oleg Yazyev, Lei Wang, Quansheng Wu, Romain Fournier

Inverse problems are encountered in many domains of physics, with analytic continuation of the imaginary Green's function into the real frequency domain being a particularly important example. However, the analytic continuation problem is ill defined and c ...

AMER PHYSICAL SOC2020

Linear and quadratic magnetoresistance in the semimetal SiP2

Oleg Yazyev, Quansheng Wu, Shengnan Zhang, Huancheng Chen

Multiple mechanisms for extremely large magnetoresistance (XMR) found in many topologically nontrivial/trivial semimetals have been theoretically proposed, but experimentally it is unclear which mechanism is responsible in a particular sample. In this pape ...

AMER PHYSICAL SOC2020

Observation of Weyl Nodes in Robust Type-II Weyl Semimetal WP2

Oleg Yazyev, Joël Mesot, Gabriel Albert Autes, Quansheng Wu

Distinct to type-I Weyl semimetals (WSMs) that host quasiparticles described by the Weyl equation, the energy dispersion of quasiparticles in type-II WSMs violates Lorentz invariance and the Weyl cones in the momentum space are tilted. Since it was propose ...

AMER PHYSICAL SOC2019