Operation of a four-qubit device in isotopically enriched Si/SiGe

Quantum processors based on electron spins in silicon are rapidly becoming a strong contender in the race to build a quantum computer. Over the past few years, quantum-dot spin qubits have been shown to offer high fidelity single-qubit [1] and two-qubit [2-5] control at levels approaching the fault tolerant threshold. However, most experiments have been conducted in one-qubit, or two-qubit devices. Recently, we have demonstrated operation of a four-qubit device in isotopically enriched Si/SiGe [6]. Here we outline improvements to our four-qubit device design and present new data on one- and two-qubit operation in the device including recent randomized benchmarking results.
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[4] Huang et al., Nature 569, 532 (2019)
[5] Xue et al., Phys. Rev. X 9, 021011 (2019)
[6] Sigillito et al., Phys. Rev. Applied 6, 061006 (2019)