Related papers: Discrete Scale Invariance in Topological Semimetal…
Topological semimetals have recently attracted great attention due to prospective applications governed by their peculiar Fermi surfaces. Weyl semimetals host chiral fermions that manifest as pairs of non-degenerate massless Weyl points in…
The recent discoveries of Dirac fermions in graphene and on the surface of topological insulators have ignited worldwide interest in physics and materials science. A Weyl semimetal is an unusual crystal where electrons also behave as…
We study the effects of strong $1/r$ long-range Coulomb interactions in a Weyl semimetal. We consider a three-dimensional (3D) Dirac fermion system on a lattice with a time-reversal symmetry breaking term, and take into account $1/r$…
We calculate the extremal cross sectional areas and cyclotron masses for the Fermi-surface pockets in Dirac and Weyl topological semimetals. The calculation is carried out for the most general form of the electron energy bands in the…
Bi$_{1-x}$Sb$_x$ is a topological insulator (TI) for $x \approx 0.03 $--$0.20$. Close to the Topological phase transition at $x = 0.03$, a magnetic field induced Weyl semi-metal (WSM) state is stabilized due to the splitting of the Dirac…
Topological phases of matter have established a new paradigm in physics, bringing quantum phenomena to the macroscopic scale and hosting exotic emergent quasiparticles. In this thesis, I theoretically and experimentally demonstrate with my…
Weyl fermions, which are fermions with definite chiralities, can give rise to anomalous breaking of the symmetry of the physical system which they are a part of. In their (3+1)-dimensional realizations in condensed matter systems, i.e., the…
We theoretically study the interplay between bulk Weyl electrons and magnetic topological defects, including magnetic domains, domain walls, and $\mathbb{Z}_6$ vortex lines, in the antiferromagnetic Weyl semimetals \mnsn\ and Mn$_3$Ge with…
The effective low energy description of interacting Dirac and Weyl semimetals is that of massless quantum electrodynamics with several Lorentz breaking material parameters. We perform a renormalization group analysis of Coulomb interaction…
Topological semimetals, such as the Weyl and Dirac semimetals, represent one of the most active research fields in modern condensed matter physics. The peculiar physical properties of these systems mainly originate from their underlying…
Topological semimetals in three dimensions display band-touchings at points (Weyl or Dirac semimetals) or nodal lines in the Brillouin zone. Weyl semimetals can occur with internal symmetries only (time-reversal ${\cal T}$, charge…
Magnets, with topologically-nontrivial Dirac/Weyl points, have recently attracted significant attention owing to the unconventional physical properties, such as large anomalous Hall effects. However, they typically have a high carrier…
In the ferromagnetic (FM) Weyl semimetal CeAlSi both space-inversion and time-reversal symmetries are broken. Our quantum oscillation (QO) data indicate that the FM ordering modifies the Fermi surface topology and also leads to an unusual…
Three-dimensional (3D) topological Weyl semimetals (TWSs) represent a novel state of quantum matter with unusual electronic structures that resemble both a "3D graphene" and a topological insulator by possessing pairs of Weyl points…
We provide a review of recent experimental results on the chiral anomaly in Dirac/Weyl semimetals. After a brief introduction, we trace the steps leading to the prediction of materials that feature protected 3D bulk Dirac nodes. The chiral…
WTe$_2$ is one of a series of recently discovered high mobility semimetals, some of whose properties are characteristic of topological Dirac or Weyl metals. One of its most interesting properties is the unsaturated giant magnetoresistance…
Rare-earth magnets with parent cubic symmetry exhibit unique topological properties. However, the origin of these behaviors remains presently unclear. Here, we develop minimal models for Dirac semimetals (DSMs) with accidental band…
Symmetry protected Dirac semimetals can be transformed into Weyl semimetals by breaking the protecting symmetry, leading to many exotic quantum phenomena such as chiral anomaly and anomalous Hall effect. Here we show that, due to the large…
Following the intense studies on topological insulators, significant efforts have recently been devoted to the search for gapless topological systems. These materials not only broaden the topological classification of matter but also…
We review recent theoretical and experimental developments in magnetic Weyl semimetals, focusing on the electromagnetic responses emerging from the interplay of their electronic band topology and magnetism. We begin by introducing the…