Commutator of Electric Charge and Magnetic Flux

Abstract

Here one can find a derivation of the commutator of the charge and magnetic flux in a superconducting circuit containing a Josephson junction from the commutation relation of quantum-field operators of electric field and vector potential. A commutator of the fluxes of electric and magnetic fields passing through two interlinked loops in vacuum is also evaluated and physical interpretation of the commutator is discussed.