Fermi Arcs and DC Transport in Nanowires of Dirac and Weyl Semimetals

Abstract

The transport properties and electron states in cylinder nanowires of Dirac and Weyl semimetals are studied paying special attention to the structure and properties of the surface Fermi arcs. The latter make the electric charge and current density distributions in nanowires strongly nonuniform as the majority of the charge density is accumulated at the surface. It is found that a Weyl semimetal wire also supports a magnetization current localized mainly at the surface because of the Fermi arcs contribution. By using the Kubo linear response approach, the direct current (DC) conductivity is calculated and it is found that its spatial profile is nontrivial. By explicitly separating the contributions of the surface and bulk states, it is shown that when the electric chemical potential and/or the radius of the wire is small, the electron transport is determined primarily by the Fermi arcs and the electrical conductivity is much higher at the surface than in the bulk. Due to the rise of the surface‐bulk transition rate, the relative contribution of the surface states to the total conductivity gradually diminishes as the chemical potential increases. In addition, the DC conductivity at the surface demonstrates noticeable peaks when the Fermi level crosses energies of the surface states.

Chiral anomaly trapped in Weyl metals: Nonequilibrium valley polarization at zero magnetic field

“…where we again used (31). This rough estimate is in qualitative agreement with the numerical results.…”

“…For larger ξ, direct scattering between the valleys becomes strongly suppressed and the relaxation of µ + − µ − must go via surface states. Thereby the relaxation along the arcs and the scattering from surface to bulk is much faster than the scattering from bulk to surface, see (31). The scattering length l c is thus set by the bulk-surface scattering length l bs , which is proportional to the ratio…”

“…Finite-size effects in meso-and macroscopic Weyl semimetals (crystal dimensions much larger than the lattice constant), have also been explored with the focus on the role of topological Fermi-arc surface states [26][27][28][29][30][31][32][33][34][35][36]. Peculiarities are rooted in the specifics of the momentum-space structure of Fermi arcs connecting valleys of opposite chirality and their unidirectional motion at a single surface, see Fig.…”

Dynamic Quantum Matter

“…In their original article, P. O. Sukhachov et al [8] examines the transport properties and electron states in nanowires of Dirac and Weyl semimetals. Dirac quantum matter exhibits a four-fold symmetry.…”

Conductance oscillation in surface junctions of Weyl semimetals

“…Most experiments on Weyl semimetals focus on the angle-resolved photoemission spectroscopy, in which the existence of FAs has been confirmed. There are also theoretical studies of the FA and its transport properties [40][41][42][43][44], like quasiparticle interference (QPI) [45,46]. Recent progress has also shown that the configurations of the FAs are sensitive to the details of the sample boundary [47][48][49], thus opening the possibility for engineering FAs and exploring their novel effects and potential applications through surface device fabrication and transport measurements.…”