Robust Trapped-Ion Quantum Logic Gates by Continuous Dynamical Decoupling

TL;DR

This paper proposes a new method for implementing high-fidelity trapped-ion quantum gates by combining phonon-mediated interactions with continuous dynamical decoupling, reducing noise sensitivity and removing the need for ground-state cooling.

Contribution

It introduces a theoretically validated scheme that enhances quantum gate fidelity through strong driving, offering robustness against noise and ac-Stark shifts without ground-state cooling.

Findings

Decouples qubits from magnetic noise via strong driving

Achieves robustness to ac-Stark shifts

Does not require ground-state cooling

Abstract

We introduce a novel scheme that combines phonon-mediated quantum logic gates in trapped ions with the benefits of continuous dynamical decoupling. We demonstrate theoretically that a strong driving of the qubit decouples it from external magnetic-field noise, enhancing the fidelity of two-qubit quantum gates. Moreover, the scheme does not require ground-state cooling, and is inherently robust to undesired ac-Stark shifts. The underlying mechanism can be extended to a variety of other systems where a strong driving protects the quantum coherence of the qubits without compromising the two-qubit couplings.