Related papers: Electronic properties of strained double-Weyl syst…

We hypothesize that in a non-metallic crystalline structure under extreme pressures, atomic wavefunctions deform to adopt a reduced rotational symmetry consistent with minimizing interstitial space in the crystal. We exemplify with a simple…

Weyl fermions are powerful yet simple entities that connect geometry, topology, and physics. While their existence as fundamental particles is still uncertain, growing evidence shows they emerge as quasiparticles in special materials called…

By virtue of being atomically thin, the electronic properties of heterostructures built from two-dimensional materials are strongly influenced by atomic relaxation. The atomic layers behave as flexible membranes rather than rigid crystals.…

The crystal lattice of a complex compound may contain a subsystem of ions with each one possessing two close equilibrium positions (double-well structure). For example, the oxygen ions in the cuprates form such a subsystem. In such a…

We study the effect of the strain on the band structure and the valley-dependent transport property of graphene heterojunctions. It is found that valley-dependent separation of electrons can be achieved by utilizing the strain and on-site…

Graphite is an example of a layered material that can be bent to form fullerenes which promise important applications in electronic nanodevices. The spheroidal geometry of a slightly elliptically deformed sphere was used as a possible…

When a crystal becomes thinner and thinner to the atomic level, peculiar phenomena discretely depending on its layer-numbers (n) start to appear. The symmetry and wave functions strongly reflect the layer-numbers and stacking order, which…

The localisation of electrons in a lattice potential is an quantum-mechanical phenomenon and is often associated with remarkable physical properties of solids involving electron spins, electric polarisations and topological effects. In…

The high mechanical strength and excellent flexibility of 2D materials such as graphene are some of their most important properties [1]. Good flexibility is key for exploiting 2D materials in many emerging technologies, such as wearable…

We study the influence of lattice deformations on the optical conductivity of a two-dimensional electron gas. Lattice deformations are taken into account by introducing a non-abelian gauge field into the Eucledian action of two-dimensional…

Weyl semimetal (WSM) is an exotic topological state in condensed matter physics. In this paper, based on a two-band cubic lattice model, we studied WSMs with a pair of tunable Weyl nodes. It is pointed out that there exist three types of…

Weyl photons appear when two three-dimensional photonic bands with linear dispersion are degenerate at a single momentum point, labeled as Weyl point. These points have remarkable properties such as being robust topological monopoles of…

A low twist angle between the two stacked crystal networks in bilayer graphene enables self-organized lattice reconstruction with the formation of a periodic domain. This superlattice modulates the vibrational and electronic structures,…

Electronic nematic order is a correlated phase of matter in which low-energy electronic states spontaneously break a discrete rotational symmetry of a crystal lattice. Bilinear coupling between the electronic nematic and strains of the same…

We study the dynamics of two strongly-interacting fermions moving in 2D lattices under the action of a periodic electric field, both with and without a magnetic flux. Due to the interaction, these particles bind together forming a doublon.…

Atomically thin van der Waals materials provide a highly tunable platform for exploring emergent quantum phenomena in solid state systems. Due to their remarkable mechanical strength, one enticing tuning knob is strain. However, the weak…

$\mathsf{Mn_{3}Sn}$ has recently attracted considerable attention as a magnetic Weyl semimetal exhibiting concomitant transport anomalies at room temperature. The topology of the electronic bands, their relation to the magnetic ground state…

In scenarios where electrons are confined to a flat surface, such as graphene, quantizing electrodynamics reveals intriguing insights. We find that one of Maxwell's equations manifests as part of the Hamiltonian, leading to novel…

Semiclassical dynamics of Bloch electrons in a crystal under slowly varying deformation is developed in the geometric language of a lattice bundle. Berry curvatures and gradients of energy are introduced in terms of lattice covariant…

The system of cold two-level atoms inside an optical lattice potential has been used to simulate various models encountered in fundamental and condensed-matter physics. When the optical lattice is periodically shaken, some interesting…