Electrical conductivity and screening effect of spin-1 chiral fermions scattered by charged impurities

We theoretically study the quantum transport in a three-dimensional spin-1 chiral fermion system in the presence of Coulomb impurities based on the self-consistent Born approximation. We find that the flat-band states anomalously enhance the screening effect, and the electrical conductivity is increased in the low-energy region. It is also found that reducing the screening length leads to an increase in the forward-scattering contribution and, thus, an increase in the vertex correction in the high-energy region.