Robust two-qubit gates for semiconductor spin qubits based on dynamical dimensionality reduction
Phys. Rev. A 114, 022613 – Published 12 August, 2026
DOI: https://doi.org/10.1103/gkrd-lm18
Abstract
High-fidelity two-qubit gates leverage qubit-qubit interactions and are essential for scalable quantum computation. However, environmental noise and imperfect control of the interactions are inevitable, which degrade the quality of gate operations. Here we introduce local microwave driving in conventional exchange-coupled semiconductor spin qubits and find that this can provide sufficient degrees of freedom to suppress various errors. Specifically, under specific driving configurations, we find that the two-qubit quantum dynamics can be mapped to lower-dimensional or Lie algebraic structures. Thus, combining this mapping with filter-function theory and truncated Fourier pulse shaping, the robust quantum control of two qubits can be simplified as a pulse optimization problem for a quantum two-level system. Numerical simulations show that our optimized controlled phase and gates maintain high fidelities, with typical errors under realistic conditions. Therefore, our protocol offers a promising alternative for robust quantum control.