Insufficiency of avoided crossings for witnessing large-scale quantum coherence in flux qubits
Florian Fröwis, Benjamin Yadin, Nicolas Gisin · Physical Review A · 2018
The generation of ``Schr\"odinger-cat'' states with superconducting devices is scrutinized. While the size of the cat cannot be quantified by standard measurements of avoided crossings, another metric is shown to appropriately witness large-scale quantum coherence.