Related papers: Measuring the Berry phase of graphene from wavefro…
Friedel oscillation is a well-known wave phenomenon, which represents the oscillatory response of electron waves to imperfection. By utilizing the pseudospin-momentum locking in gapless graphene, two recent experiments demonstrate the…
Chiral quasiparticles in Bernal-stacked bilayer graphene have valley-contrasting Berry phases of 2{\pi}. This nontrival topological structure, associated with the pseudospin winding along a closed Fermi surface, is responsible for various…
The electronic properties of graphene have been intensively investigated over the last decade, and signatures of the remarkable features of its linear Dirac spectrum have been displayed using transport and spectroscopy experiments. In…
Brillouin zones of graphene systems possess Dirac points, where band degeneracies occur. We study the variety of (and large magnitude) phases that the electronic states can acquire when a uniform time-dependent electric field carries the…
The wavefront dislocation is an important and ubiquitous phenomenon in wave fields. It is closely related to the phase singularity in a wave function. Some recent studies have verified that the wavefront dislocations in the local density of…
Berry phase is one of the key elements to understand quantum-mechanical phenomena such as the Aharonov-Bohm effect and the unconventional Hall effect in graphene. The Berry phase in monolayer and bilayer graphene has been manifested by the…
The physics of massless relativistic quantum particles has recently arisen in the electronic properties of solids following the discovery of graphene. Around the accidental crossing of two energy bands, the electronic excitations are…
We demonstrate that dislocations in the graphene lattice give rise to electron Berry phases equivalent to quantized values {0,1/3,-1/3} in units of the flux quantum, but with an opposite sign for the two valleys. An elementary scale…
The electronic dispersion of a graphene bilayer is highly dependent on rotational mismatch between layers and can be further manipulated by electrical gating. This allows for an unprecedented control over electronic properties and opens up…
Displacement field control of elecronic bands in low-dimensional systems is a promising route toward engineering emergent quantum phases. Here, we report displacement-field-induced band inversion and modulation of the Berry phase of…
Electron motion in crystals is governed by the coupling between crystal momentum and internal degrees of freedom such as spin implicit in the band structure. The description of this coupling in terms of a momentum-dependent effective field…
Ever since the novel quantum Hall effect in bilayer graphene was discovered, and explained by a Berry phase of 2pi [K. S. Novoselov et al., "Unconventional quantum Hall effect and Berry's phase of 2pi in bilayer graphene", Nature Phys. 2,…
The topological structure of the wavefunctions of particles in periodic potentials is characterized by the Berry curvature $\Omega_{kn}$ whose integral on the Brillouin zone is a topological invariant known as the Chern number. The…
It has been recently established that optoelectronic and non-linear transport experiments can give direct access to the dipole moment of the Berry curvature in non-magnetic and non-centrosymmetric materials. Thus far, non-vanishing Berry…
The anomalous Hall effect in time-reversal symmetry broken systems is underpinned by the concept of Berry curvature in band theory. However, recent experiments reveal that the nonlinear Hall effect can be observed in non-magnetic systems…
The ability to engineer the electronic band structure and, more strikingly, to access new exotic phase of matter has been the cornerstone of the advance of science and technology. Twisting van der Waals materials to form moir\'e…
The Berry curvature (BC) - a quantity encoding the geometric properties of the electronic wavefunctions in a solid - is at the heart of different Hall-like transport phenomena, including the anomalous Hall and the non-linear Hall and Nernst…
Topological aspects of electron wavefunction play a crucial role in determining the physical properties of materials. Berry curvature and Chern number are used to define the topological structure of electronic bands. While Berry curvature…
We study the energy spectrum and electronic properties of graphene in a periodic magnetic field of zero average with a symmetry of triangular lattice. The periodic field leads to formation of a set of minibands separated by gaps, which can…
Though the observation of the quantum anomalous Hall effect and nonlocal transport response reveals nontrivial band topology governed by the Berry curvature in twisted bilayer graphene, some recent works reported nonlinear Hall signals in…