Boltzmann equation approach to anomalous transport in a Weyl metal

Weyl metal is regarded as a platform toward interacting topological states of matter, where its topological structure gives rise to anomalous transport phenomena, referred to as chiral magnetic effect and ``negative'' magnetoresistivity, the origin of which is chiral anomaly. Recently, the negative magnetoresistivity has been observed with the signature of weak antilocalization at $x=3--4%$ in Bi_1-x{Sb}ₓ$, where a magnetic field is applied in parallel with an electric field (${E}{{0.16em}{0ex}}{∥}{{0.16em}{0ex}}{B}$). Based on the Boltzmann equation approach, we find the negative magnetoresistivity in the presence of weak antilocalization. An essential ingredient is to introduce the topological structure of chiral anomaly into the Boltzmann equation approach, resorting to semiclassical equations of motion with Berry curvature.