Generation of high-fidelity CNOT logic gates by coupled superconducting qubits
نویسنده
چکیده
Building on the previous results of the Weyl chamber steering method, we demonstrate how to generate high-fidelity CNOT by direct application of certain, physically relevant Hamiltonians with fixed coupling constants containing Rabi terms. Such Hamiltonians are often used to describe two superconducting qubits driven by local rf-pulses. It is found that in order to achieve 100% fidelity in a system with capacitive coupling of strength g one Rabi term suffices. We give the exact values of the physical parameters needed to implement such CNOT. The gate time and all possible Rabi frequencies are found to be t = π/(2g) and Ω1/g = √ 64n2 − 1, n = 1, 2, 3, . . .. Generation of a perfect CNOT in a system with inductive coupling, characterized by additional constant k, requires the presence of both Rabi terms. The gate time is again t = π/(2g), but now there is an infinite number of solutions, each of which is valid in a certain range of k and is characterized by a pair of integers (n,m),
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