Decoherence of a Superposition of Macroscopic Current States in a SQUID

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.

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Cited by in corpus (5)

• Experimental motivation and empirical consistency in minimal no-collapse quantum mechanics
• Universal Decoherence in Solids
• Conservation of Angular Momentum in the Elastic Medium with Spins
• Reply to "Comment on Universal Decoherence in Solids"
• A Chain-Boson Model for the Decoherence and Relaxation of a Few Coupled SQUIDs in a Phonon Bath