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A n-qubit controlled phase gate with superconducting quantum interference devices coupled to a resonator

Chui-Ping Yang·Siyuan Han
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Abstract

We present a way to realize a $n$-qubit controlled phase gate with superconducting quantum interference devices (SQUIDs) by coupling them to a superconducting resonator. In this proposal, the two logical states of a qubit are represented by the two lowest levels of a SQUID. An intermediate level of each SQUID is utilized to facilitate coherent control and manipulation of quantum states of the qubits. It is interesting to note that a $n$-qubit controlled phase gate can be achieved with $n$ SQUIDs by successively applying a $π/2$ Jaynes-Cummings pulse to each of the $n-1$ control SQUIDs before and after a $π$ Jaynes-Cummings pulse on the target SQUID.

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Chui-Ping Yang, Siyuan Han. 2005-06-24. A n-qubit controlled phase gate with superconducting quantum interference devices coupled to a resonator. https://doi.org/10.1103/physreva.72.032311

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