Negative longitudinal magnetoresistance in Dirac and Weyl metals

Understand

It has recently been found that Dirac and Weyl metals are characterized by an unusual weak-field longitudinal magnetoresistance: large, negative, and quadratic in the magnetic field.

• This has been shown to arise from chiral anomaly, i.e.
• nonconservation of the chiral charge in the presence of external electric and magnetic fields, oriented collinearly.
• In this paper we report on a theory of this effect in both Dirac and Weyl metals.