# Detection of a Schroedinger's Cat State in an rf-SQUID

@article{Friedman2000DetectionOA, title={Detection of a Schroedinger's Cat State in an rf-SQUID}, author={Jonathan R Friedman and Vijay Patel and W. Chen and Sergey K. Tolpygo and James E. Lukens}, journal={arXiv: Mesoscale and Nanoscale Physics}, year={2000} }

We present experimental evidence for a coherent superposition of macroscopically distinct flux states in an rf-SQUID. When the external flux Phi_x applied to the SQUID is near 1/2 of a flux quantum Phi_0, the SQUID has two nearly degenerate configurations: the zero- and one-fluxoid states, corresponding to a few microamperes of current flowing clockwise or counterclockwise, respectively. The system is modeled as a particle in a double-well potential where each well represents a distinct fluxoid… Expand

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