Noise Robustness Analysis and Process Tomography for Adiabatic Rydberg Gates*

Neutral atom arrays are some of the most promising quantum computing platforms due to their scalability and connectivity. However, similar to other platforms, multi-qubit gate imperfections present a major barrier to realizing practical quantum algorithms. Theoretical studies have shown the ability to realize highly accurate CZ gates with F ~ 0.9998 [1], well above the threshold of fault-tolerant quantum computing.  However, recent experiments have only demonstrated CZ gates with F ~ 0.97 in 1D array [2] and F ~ 0.89[3] and 0.96[4] in 2D arrays. This work develops techniques that aim to improve the demonstrated fidelities and bridge the gap between theory and experiment.

In this work, we make three contributions. First, we analyze the noise robustness of various Rydberg CZ gate protocols and develop improved protocols that will be better suited to tolerate control imperfections in future experiments. Second, we use quantum process tomography and leakage analysis to characterize the error types in those gate protocols. Finally, we perform gate optimization that suppresses specific types of errors with the eventual goal of developing error correction protocols that enable fault-tolerant quantum computing with neutral atoms.