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تسجيل مستخدم جديدSuperconductivity provides access to the chiral magnetic effect of an unpaired Weyl cone
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The massless fermions of a Weyl semimetal come in two species of opposite chirality, in two cones of the band structure. As a consequence, the current $j$ induced in one Weyl cone by a magnetic field $B$ (the chiral magnetic effect, CME) is cancelled in equilibrium by an opposite current in the other cone. Here we show that superconductivity offers a way to avoid this cancellation, by means of a flux bias that gaps out a Weyl cone jointly with its particle-hole conjugate. The remaining gapless Weyl cone and its particle-hole conjugate represent a single fermionic species, with renormalized charge $e^ast$ and a single chirality $pm$ set by the sign of the flux bias. As a consequence, the CME is no longer cancelled in equilibrium but appears as a supercurrent response $partial j/partial B=pm(e^ast e/h^2)mu$ along the magnetic field at chemical potential $mu$.
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