Decoherence of a Superposition of Macroscopic Current States in a SQUID
arXiv:cond-mat/0211246 · doi:10.1103/PhysRevB.67.064515
Abstract
We show that fundamental conservation laws mandate parameter-free mechanisms of decoherence of quantum oscillations of the superconducting current between opposite directions in a SQUID -- emission of phonons and photons at the oscillation frequency. The corresponding rates are computed and compared with experimental findings. The decohering effects of external mechanical and magnetic noise are investigated.