Correlation effects in double-Weyl semimetals

Abstract

We study the long-range Coulomb interaction effects on the double-Weyl fermion system, which is possibly realized in the three-dimensional semimetal ${\mathrm{HgCr}}_{2}{\mathrm{Se}}_{4}$ in the ferromagnetic phase. Within the one-loop renormalization-group analysis, we find that there exists a stable fixed point at which the Coulomb interaction is screened anisotropically. At the stable fixed point, the renormalized Coulomb interaction induces nontrivial logarithmic corrections to the physical quantities, such as specific heat, compressibility, the electrical conductivity, and the diamagnetic susceptibility that are obtained utilizing the renormalization-group equations.