Publications de Gabriel Albert Autes

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

Dynamic media content categorisation method

Sabine Süsstrunk, Gabriel Albert Autes, Mahmut Sami Arpa

The present invention concerns a method of classifying a media item into a user profile suitability class in a classification system comprising a set of pre-trained artificial neural networks. The method comprising: receiving (101) a media file; extracting ...

2020

Topological Fermi-arc surface resonances in bcc iron

Oleg Yazyev, Gabriel Albert Autes, Daniel Gosalbez Martinez

The topological classification of matter has been extended to include semimetallic phases characterized by the presence of topologically protected band degeneracies. In Weyl semimetals, the foundational gapless topological phase, chiral degeneracies are is ...

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

Electronic properties of incommensurately modulated novel and complex materials

László Forró, Oleg Yazyev, Alla Arakcheeva, Ana Akrap, Gabriel Albert Autes, Sergiy Katrych, Edoardo Martino, Philip Johannes Walter Moll

INT UNION CRYSTALLOGRAPHY2018

Persistence of a surface state arc in the topologically trivial phase of MoTe2

Helmuth Berger, Philippe Bugnon, Marco Grioni, Arnaud Magrez, Oleg Yazyev, Alberto Crepaldi, Gabriel Albert Autes

The prediction of Weyl fermions in the low-temperature noncentrosymmetric 1T' phase of MoTe2 still awaits clear experimental confirmation. Here, we report angle-resolved photoemission (ARPES) data and ab initio calculations that reveal a surface state arc ...

Amer Physical Soc2017

Two-Orbital Kondo Screening in a Self-Assembled Metal Organic Complex

Harald Brune, Stefano Rusponi, Oleg Yazyev, Marina Pivetta, Fabio Donati, Luca Gragnaniello, Gabriel Albert Autes, Giulia Elisabetta Pacchioni

Iron atoms adsorbed on a Cu(111) surface and buried under polyphenyl dicarbonitrile molecules exhibit strongly spatial anisotropic Kondo features with directionally dependent Kondo temperatures and line shapes, as evidenced by scanning tunneling spectrosco ...

American Chemical Society2017

BiTeCl and BiTeBr: A comparative high-pressure optical study

Helmuth Berger, Philippe Bugnon, Arnaud Magrez, Oleg Yazyev, Ana Akrap, Gabriel Albert Autes

We here report a detailed high-pressure infrared transmission study of BiTeCl and BiTeBr. We follow the evolution of two band transitions: the optical excitation beta between two Rashba-split conduction bands, and the absorption. across the band gap. In th ...

Amer Physical Soc2017

A novel quasi-one-dimensional topological insulator in bismuth iodide beta-Bi4I4

László Forró, Marco Grioni, Oleg Yazyev, Luca Moreschini, Gabriel Albert Autes, Jens Christian Johannsen, Andrea Pisoni, Wentao Zhang

Recent progress in the field of topological states of matter(1,2) has largely been initiated by the discovery of bismuth and antimony chalcogenide bulk topological insulators (TIs; refs 3-6), followed by closely related ternary compounds(7-16) and predicti ...

Nature Publishing Group2016

Evidence for a Strong Topological Insulator Phase in ZrTe5

Helmuth Berger, Philippe Bugnon, Arnaud Magrez, Oleg Yazyev, Alberto Crepaldi, Luca Gragnaniello, Gabriel Albert Autes

The complex electronic properties of ZrTe5 have recently stimulated in-depth investigations that assigned this material to either a topological insulator or a 3D Dirac semimetal phase. Here we report a comprehensive experimental and theoretical study of bo ...

Amer Physical Soc2016

Robust Type-II Weyl Semimetal Phase in Transition Metal Diphosphides XP2 (X = Mo, W)

Oleg Yazyev, Gabriel Albert Autes

The recently discovered type-II Weyl points appear at the boundary between electron and hole pockets. Type-II Weyl semimetals that host such points are predicted to exhibit a new type of chiral anomaly and possess thermodynamic properties very different fr ...

Amer Physical Soc2016

Observation of Weyl nodes and Fermi arcs in tantalum phosphide

Oleg Yazyev, Joël Mesot, Kazimierz Conder, Gabriel Albert Autes

A Weyl semimetal possesses spin-polarized band-crossings, called Weyl nodes, connected by topological surface arcs. The low-energy excitations near the crossing points behave the same as massless Weyl fermions, leading to exotic properties like chiral anom ...

Nature Publishing Group2016

Localized electronic states at grain boundaries on the surface of graphene and graphite

Oleg Yazyev, Gabriel Albert Autes

Recent advances in large-scale synthesis of graphene and other 2D materials have underscored the importance of local defects such as dislocations and grain boundaries (GBs), and especially their tendency to alter the electronic properties of the material. ...

Iop Publishing Ltd2016

Electromechanical oscillations in bilayer graphene

Mohamed Malik Benameur, Andras Kis, Oleg Yazyev, Mahmut Tosun, Fernando Gargiulo, Gabriel Albert Autes, Sajedeh Manzeli

Nanoelectromechanical systems constitute a class of devices lying at the interface between fundamental research and technological applications. Realizing nanoelectromechanical devices based on novel materials such as graphene allows studying their mechanic ...

Nature Research2015

Engineering the topological surface states in the (Sb2)m−Sb2Te3(m=0–3) superlattice serie

Helmuth Berger, Philippe Bugnon, Marco Grioni, Arnaud Magrez, Oleg Yazyev, Alberto Crepaldi, Simon Karl Moser, Gabriel Albert Autes, Jens Christian Johannsen

We investigate the evolution of both the occupied and unoccupied electronic structure in representative compounds of the infinitely adaptive superlattice series (Sb2)m−Sb2Te3 (m=0–3) by means of angle-resolved photoemission spectroscopy and time-delayed tw ...

Amer Physical Soc2015

Bulk and surface band structure of the new family of semiconductors BiTeX (X=I, Br, Cl)

Helmuth Berger, Philippe Bugnon, Marco Grioni, Arnaud Magrez, Oleg Yazyev, Luca Moreschini, Alberto Crepaldi, Simon Karl Moser, Gabriel Albert Autes, Jens Christian Johannsen

We present an overview of the new family of semiconductors BiTeX (X = I, Br, Cl) from the perspective of angle resolved photoemission spectroscopy. The strong band bending occurring at the surface potentially endows them with a large flexibility, as they a ...

Elsevier2015

Controlled growth of a line defect in graphene and implications for gate-tunable valley filtering

Oleg Yazyev, Fernando Gargiulo, Gabriel Albert Autes, Jie Chen

Atomically precise tailoring of graphene can enable unusual transport pathways and new nanometer-scale functional devices. Here we describe a recipe for the controlled production of highly regular "5-5-8" line defects in graphene by means of simultaneous e ...

Amer Physical Soc2014

Atomic and electronic structure of a Rashba p-n junction at the BiTeI surface

Helmuth Berger, Philippe Bugnon, Marco Grioni, Oleg Yazyev, Gabriel Albert Autes, Cédric Tournier-Colletta

The non-centro-symmetric semiconductor BiTeI exhibits two distinct surface terminations that support spin-split Rashba surface states. Their ambipolarity can be exploited for creating spin-polarized p-n junctions at the boundaries between domains with diff ...

American Physical Society2014

Momentum and photon energy dependence of the circular dichroic photoemission in the bulk Rashba semiconductors BiTeX (X = I, Br, Cl)

Helmuth Berger, Philippe Bugnon, Marco Grioni, Arnaud Magrez, Oleg Yazyev, Luca Moreschini, Alberto Crepaldi, Gabriel Albert Autes, Cédric Tournier-Colletta, Jens Christian Johannsen

Bulk Rashba systems BiTeX (X = I, Br, Cl) are emerging as important candidates for developing spintronics devices because of the coexistence of spin-split bulk and surface states, along with the ambipolar character of the surface charge carriers. The need ...

American Physical Society2014

Infrared- and Raman-Spectroscopy Measurements of a Transition in the Crystal Structure and a Closing of the Energy Gap of BiTeI under Pressure

Oleg Yazyev, Ana Akrap, Gabriel Albert Autes, Dirk Van der Marel

BiTeI is a giant Rashba spin splitting system, in which a noncentrosymmetric topological phase has recently been suggested to appear under high pressure. We investigated the optical properties of this compound, reflectivity and transmission, under pressure ...

American Physical Society2014