The size of macroscopic superposition states in flux qubits

Abstract

The question as to whether or not quantum mechanics is applicable to the macroscopic scale has motivated efforts to generate superposition states of macroscopic numbers of particles and to determine their effective size. Superpositions of circulating current states in flux qubits constitute candidate states that have been argued to be at least mesoscopic. We present a microscopic analysis that reveals the number of electrons participating in these superpositions to be surprisingly but not trivially small, even though differences in macroscopic observables are large.

7 pages, no figures

References in corpus (4)

• Coherent Quantum Dynamics of a Superconducting Flux Qubit
• A measurement-based measure of the size of macroscopic quantum superpositions
• Measuring the size of a Schroedinger cat state
• Electronic structure of superposition states in flux qubits

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