Universal chiral magnetic effect in the vortex lattice of a Weyl superconductor

Abstract It was shown recently that Weyl fermions in a superconducting vortex lattice can condense into Landau levels. Here we study the chiral magnetic effect in the lowest Landau level: The appearance of an equilibrium current I along the lines of magnetic flux Φ , due to an imbalance between Weyl fermions of opposite chirality. A universal contribution d I ∕ d Φ = ( e ∕ h ) 2 μ (at equilibrium chemical potential μ relative to the Weyl point) appears when quasiparticles of one of the two chiralities are confined in vortex cores. The confined states are charge-neutral Majorana fermions.