First-Order Crosstalk Mitigation in Parallel Quantum Gates Driven With Multi-Photon Transitions
Abstract
We demonstrate an order of magnitude reduction in the sensitivity to optical crosstalk for neighboring trapped-ion qubits during simultaneous single-qubit gates driven with individual addressing beams. Gates are implemented via two-photon Raman transitions, where crosstalk is mitigated by offsetting the drive frequencies for each qubit to avoid first-order crosstalk effects from inter-beam two-photon resonance. The technique is simple to implement, and we find that phase-dependent crosstalk due to optical interference is reduced on the most impacted neighbor from a maximal fractional rotation error of 0.185(4) without crosstalk mitigation to 0.006 with the mitigation strategy. Further, we characterize first-order crosstalk in the two-qubit gate and avoid the resulting rotation errors for the arbitrary-axis M{\o}lmer-S{\o}rensen gate via a phase-agnostic composite gate. Finally, we demonstrate holistic system performance by constructing a composite CNOT gate using the improved single-qubit gates and phase-agnostic two-qubit gate. This work is done on the Quantum Scientific Computing Open User Testbed (QSCOUT); however, our methods are widely applicable for individual-addressing Raman gates and impose no significant overhead, enabling immediate improvement for quantum processors that incorporate this technique.
Cite
@article{arxiv.2309.15342,
title = {First-Order Crosstalk Mitigation in Parallel Quantum Gates Driven With Multi-Photon Transitions},
author = {Matthew N. H. Chow and Christopher G. Yale and Ashlyn D. Burch and Megan Ivory and Daniel S. Lobser and Melissa C. Revelle and Susan M. Clark},
journal= {arXiv preprint arXiv:2309.15342},
year = {2024}
}