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arXiv · 2101.08840

Single-tone pulse sequences and robust two-tone shaped pulses for three silicon spin qubits with always-on exchange

David W. Kanaar·Sidney Wolin·Utkan Güngördü·J. P. Kestner
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Abstract

Quantum computation requires high-fidelity single-qubit and two-qubit gates on a scalable platform. Silicon spin qubits are a promising platform toward realization of this goal. In this paper we show how to perform single-qubit and CZ gates in a linear chain of three spin qubits with always-on exchange coupling, which is relevant for certain dot- and donor-based silicon devices. We also show how to make the CZ gate robust against both charge noise and pulse length error using a two-tone pulse shaping method. The robust pulse maintains a fidelity of 99.99% at 3.5% fluctuations in exchange or pulse amplitude, which is an improvement over the uncorrected pulses where this fidelity can only be maintained for fluctuations in exchange up to 2% or up to 0.2% in amplitude.

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David W. Kanaar, Sidney Wolin, Utkan Güngördü, J. P. Kestner. 2021-06-22. Single-tone pulse sequences and robust two-tone shaped pulses for three silicon spin qubits with always-on exchange. https://doi.org/10.1103/physrevb.103.235314

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