Crosstalk analysis for single-qubit and two-qubit gates in spin qubit arrays

TL;DR

This paper analyzes crosstalk effects in spin qubit arrays during single- and two-qubit gates, proposing conditions to minimize crosstalk and enable scalable quantum computing with high fidelity.

Contribution

It introduces a simple Heisenberg model to analyze crosstalk impacts and proposes synchronization conditions to suppress crosstalk in scalable spin qubit systems.

Findings

Crosstalk significantly affects qubit fidelity in larger arrays.

Synchronization conditions can mitigate crosstalk effects.

Parameter sets for near crosstalk-free CNOT gates are proposed.

Abstract

Scaling up spin qubit systems requires high-fidelity single-qubit and two-qubit gates. Gate fidelities exceeding $98\%$ were already demonstrated in silicon based single and double quantum dots, whereas for the realization of larger qubit arrays crosstalk effects on neighboring qubits must be taken into account. We analyze qubit fidelities impacted by crosstalk when performing single-qubit and two-qubit operations on neighbor qubits with a simple Heisenberg model. Furthermore we propose conditions for driving fields to robustly synchronize Rabi oscillations and avoid crosstalk effects. In our analysis we also consider next to nearest neighbor crosstalk and show that double synchronization leads to a restricted choice for the driving field strength, exchange interaction, and thus gate time. Considering realistic experimental conditions we propose a set of parameter values to perform a nearly crosstalk-free CNOT gate and so open up the pathway to scalable quantum computing devices.