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Macroscopic Many-Qubit Interactions in Superconducting Flux Qubits

Sam Young Cho·Mun Dae Kim
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Abstract

Superconducting flux qubits are considered to investigate macroscopic many-qubit interactions. Many-qubit states based on current states can be manipulated through the current-phase relation in each superconducting loop. For flux qubit systems comprised of $N$ qubit loops, a general expression of low energy Hamiltonian is presented in terms of low energy levels of qubits and macroscopic quantum tunnelings between the many-qubit states. Many-qubit interactions classified by {\em Ising type- or tunnel-}exchange interactions can be observable experimentally. Flux qubit systems can provide various artificial-spin systems to study many-body systems that cannot be found naturally.

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Sam Young Cho, Mun Dae Kim. 2007-03-20. Macroscopic Many-Qubit Interactions in Superconducting Flux Qubits. https://doi.org/10.1103/physrevb.77.212506

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