Noise-resilient driven exchange gate for quantum dot spin qubits*

Spin qubits in silicon quantum dots are a promising candidate for high-fidelity quantum computation due to long decoherence times and fast operations.

Demonstrations of single qubit gates with fidelities up to 99.9% have been shown [1,2].
Recent demonstrations of two-qubit gates show fidelities of 92-98% [2,3]. These two-qubit gate implementations are not robust against low-frequency charge noise, which couples in via the exchange interaction, causing a limited fidelity. We propose a simple yet effective scheme that is resilient against low-frequency charge noise. We use a combination of analytic calculations and numerical simulations under realistic conditions to obtain estimated gate fidelities greater than 99%, which allow for fault-tolerant two qubit gates. We directly compare these realizations with existing proposals and will present our experimental efforts towards achieving this goal.


[1] Yoneda et al., Nat. Nanotechnol. 13, 102 (2018)
[2] Huang et al., Nature (London) 569, 532 (2019)
[3] Xu et al., Phys. Rev. X 9, 021011 (2019)