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arXiv · 1602.00072

Four-junction superconducting circuit

Yueyin Qiu·Wei Xiong·Xiao-Ling He·Tie-Fu Li·J. Q. You
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Abstract

We develop a theory for the quantum circuit consisting of a superconducting loop interrupted by four Josephson junctions and pierced by a magnetic flux (either static or time-dependent). In addition to the similarity with the typical three-junction flux qubit in the double-well regime, we demonstrate the difference of the four-junction circuit from its three-junction analogue, including its advantages over the latter. Moreover, the four-junction circuit in the single-well regime is also investigated. Our theory provides a tool to explore the physical properties of this four-junction superconducting circuit.

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Yueyin Qiu, Wei Xiong, Xiao-Ling He, Tie-Fu Li, J. Q. You. 2016-01-30. Four-junction superconducting circuit. https://arxiv.org/abs/1602.00072

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