Crosstalk analysis in single hole-spin qubits within highly anisotropic g-tensors

TL;DR

This paper analyzes crosstalk effects in single hole-spin qubits with anisotropic g-tensors, deriving conditions and optimized parameters to minimize crosstalk and improve qubit fidelity for scalable quantum computing.

Contribution

It introduces an analytical synchronization condition and optimized driving protocols to suppress crosstalk in anisotropic hole-spin qubits, advancing scalable quantum architecture design.

Findings

Derived an analytical crosstalk elimination condition.

Identified parameter regimes for near crosstalk-free gates.

Showed strong dependence of crosstalk mitigation on qubit anisotropy.

Abstract

Spin qubits based on valence band hole states are highly promising for quantum information processing due to their strong spin-orbit coupling and ultrafast operation speed. As these systems scale up, achieving high-fidelity single-qubit operations becomes essential. However, mitigating crosstalk effects from neighboring qubits in larger arrays, particularly for anisotropic qubits with strong spin-orbit coupling, presents a significant challenge. We investigate the impact of crosstalk on qubit fidelities during single-qubit operations and derive an analytical equation that serves as a synchronization condition to eliminate crosstalk in anisotropic media. Our analysis proposes optimized driving field conditions that can robustly synchronize Rabi oscillations and minimize crosstalk, showing a strong dependence on qubit anisotropy and the orientation of the external magnetic field. Taking experimental data into our analysis, we identify a set of parameter values that enable nearly crosstalk-free single-qubit gates, thereby paving the way for scalable quantum computing architectures.