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تسجيل مستخدم جديدHigh-fidelity two-qubit gates in silicon above one Kelvin
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Spin qubits in quantum dots define an attractive platform for scalable quantum information because of their compatibility with semiconductor manufacturing, their long coherence times, and the ability to operate at temperatures exceeding one Kelvin. Qubit logic can be implemented by pulsing the exchange interaction or via driven rotations. Here, we show that these approaches can be combined to execute a multitude of native two-qubit gates in a single device, reducing the operation overhead to perform quantum algorithms. We demonstrate, at a temperature above one Kelvin, single-qubit rotations together with the two-qubit gates CROT, CPHASE and SWAP. Furthermore we realize adiabatic, diabatic and composite sequences to optimize the qubit control fidelity and the gate time. We find two-qubit gates that can be executed within 67 ns and by theoretically analyzing the experimental noise sources we predict fidelities exceeding 99%. This promises fault-tolerant operation using quantum hardware that can be embedded with classical electronics for quantum integrated circuits.
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Universal quantum computation will require qubit technology based on a scalable platform, together with quantum error correction protocols that place strict limits on the maximum infidelities for one- and two-qubit gate operations. While a variety of
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Recent studies of silicon spin qubits at temperatures above 1 K are encouraging demonstrations that the cooling requirements for solid-state quantum computing can be considerably relaxed. However, qubit readout mechanisms that rely on charge sensing
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