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

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.

Randomized benchmarking for non-Markovian noise

“…Even though we use this as a simple theoretical construction and illustration, similar noise dynamics, albeit with many more considerations, come upon in real spin qubit quantum computers, e.g. as undesired crosstalk [65].…”

Autonomous estimation of high-dimensional Coulomb diamonds from sparse measurements

“…In machine-learning applications especially, the presence of measurement cost often leads to the deploy of active-learning algorithms to acquire only those samples that are most informative for training the model; it is therefore important to discard irrelevant data early on in the algorithmic procedure. Additionally, the crosstalk between qubits in two-and higher dimensions is predicted to become a significant operational burden [22].…”