Crosstalk analysis for simultaneously driven two-qubit gates in spin qubit arrays

TL;DR

This paper investigates crosstalk errors in spin qubit arrays during simultaneous two-qubit gates like CNOT and CPHASE, analyzing their impact and proposing control protocols to minimize errors for scalable quantum processors.

Contribution

It provides a detailed analysis of crosstalk effects during two-qubit gates and introduces control strategies to reduce errors in multi-qubit spin qubit arrays.

Findings

Crosstalk is unavoidable in parallel two-qubit gates.

Control protocols can mitigate crosstalk errors.

Analysis includes 2D arrangements of gates.

Abstract

One of the challenges when scaling up semiconductor-based quantum processors consists in the presence of crosstalk errors caused by control operations on neighboring qubits. In previous work, crosstalk in spin qubit arrays has been investigated for non-driven single qubits near individually driven quantum gates and for two simultaneously driven single-qubit gates. Nevertheless, simultaneous gates are not restricted to single-qubit operations but also include frequently used two-qubit gates such as the CNOT gate. We analyse the impact of crosstalk drives on qubit operations, such as the CNOT and CPHASE gates. We investigate the case of parallel $Y$ and CNOT gates, and we also consider a two-dimensional arrangement of two parallel CNOT gates and find unavoidable crosstalk. To minimize crosstalk errors, we develop appropriate control protocols.