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Macroscopic Quantum Resonance of Coupled Flux Qubits; A Quantum Computation Scheme

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Abstract

We show that a superconducting circuit containing two loops, when treated with Macroscopic Quantum Coherence (MQC) theory, constitutes a complete two-bit quantum computer. The manipulation of the system is easily implemented with alternating magnetic fields. A \textit{universal} set of quantum gates is deemed available by means of all unitary single bit operations and a controlled-not (\textsc{cnot}) sequence. We use multi-dimensional MQC theory and time-dependent first order perturbation theory to analyze the model. Our calculations show that a two qubit arrangement, each having a diameter of 200nm, operating in the flux regime can be operated with a static magnetic field of $\sim 0.1$T, and an alternating dynamic magnetic field of amplitude $\sim 1$ Gauss and frequency $\sim 10$Hz. The operational time $τ_{op}$ is estimated to be $\sim 10$ns.

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Hide Akisato. 2003-03-20. Macroscopic Quantum Resonance of Coupled Flux Qubits; A Quantum Computation Scheme. https://arxiv.org/abs/quant-ph/0303128

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