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arXiv · 1905.01206

Superconducting circuit protected by two-Cooper-pair tunneling

W. C. Smith·A. Kou·X. Xiao·U. Vool·M. H. Devoret
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Abstract

We present a protected superconducting qubit based on an effective circuit element that only allows pairs of Cooper pairs to tunnel. These dynamics give rise to a nearly degenerate ground state manifold indexed by the parity of tunneled Cooper pairs. We show that, when the circuit element is shunted by a large capacitance, this manifold can be used as a logical qubit that we expect to be insensitive to multiple relaxation and dephasing mechanisms.

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W. C. Smith, A. Kou, X. Xiao, U. Vool, M. H. Devoret. 2019-05-03. Superconducting circuit protected by two-Cooper-pair tunneling. https://doi.org/10.1038/s41534-019-0231-2

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