Concept

Particule de Dirac

Publications associées (35)

Chiral gravitational waves from chiral fermions

We report on a new mechanism that leads to the generation of primordial chiral gravitational waves, and hence, the violation of the parity symmetry in the Universe. We show that nonperturbative production of fermions with a definite helicity is accompanied ...

Amer Physical Soc2017

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

Marco Grioni, Arnaud Magrez, Oleg Yazyev, Helmuth Berger, Philippe Bugnon, 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

Magnetic torque anomaly in the quantum limit of Weyl semimetals

Philip Johannes Walter Moll

Electrons in materials with linear dispersion behave as massless Weyl- or Dirac-quasiparticles, and continue to intrigue due to their close resemblance to elusive ultra-relativistic particles as well as their potential for future electronics. Yet the exper ...

2016

Dirac fermions at high-index surfaces of bismuth chalcogenide topological insulator nanostructures

Oleg Yazyev, Naunidh Singh Virk

Binary bismuth chalcogenides Bi2Se3, Bi2Te3, and related materials are currently being extensively investigated as the reference topological insulators (TIs) due to their simple surface-state band dispersion (single Dirac cone) and relatively large bulk ba ...

Nature Publishing Group2016

Observation of Weyl nodes and Fermi arcs in tantalum phosphide

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

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

The classical and quantum dynamics of molecular spins on graphene

Klaus Kern, Marko Burghard, Stephan Rauschenbach

Controlling the dynamics of spins on surfaces is pivotal to the design of spintronic(1) and quantum computing(2) devices. Proposed schemes involve the interaction of spins with graphene to enable surface-state spintronics(3,4) and electrical spin manipulat ...

Nature Publishing Group2016

Observation of Weyl nodes in TaAs

Joël Mesot

In 1929, H. Weyl proposed that the massless solution of the Dirac equation represents a pair of a new type of particles, the so-called Weyl fermions1. However, their existence in particle physics remains elusive after more than eight decades. Recently, sig ...

Nature Publishing Group2015

On the effective operators for Dark Matter annihilations

Alexander Monin, Andrea De Simone, Andrea Thamm

We consider effective operators describing Dark Matter (DM) interactions with Standard Model fermions. In the non-relativistic limit of the DM field, the operators can be organized according to their mass dimension and their velocity behaviour, i.e. whethe ...

Iop Publishing Ltd2013

Evidence of reduced surface electron-phonon scattering in the conduction band of Bi2Se3 by nonequilibrium ARPES

Klaus Kern, Marco Grioni, Helmuth Berger, Philippe Bugnon, Alberto Crepaldi, Jens Christian Johannsen

The nature of the Dirac quasiparticles in topological insulators calls for a direct investigation of the electron-phonon scattering at the surface. By comparing time-resolved ARPES measurements of the topological insulator Bi2Se3 with different probing dep ...

Amer Physical Soc2013

Quantum fluctuations of one-dimensional free fermions and Fisher-Hartwig formula for Toeplitz determinants

We revisit the problem of finding the probability distribution of a fermionic number of one-dimensional spinless free fermions on a segment of a given length. The generating function for this probability distribution can be expressed as a determinant of a ...

2011

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