Individually-addressed quantum gate interactions using dynamical decoupling

TL;DR

This paper proposes a microwave-based method for individually addressing and entangling trapped ions with micron-scale spatial resolution, demonstrating suppression of unwanted interactions and modeling low crosstalk errors for multi-qubit systems.

Contribution

It introduces a microwave-driven approach for high-resolution individual ion addressing and entangling gates, with experimental validation and error modeling for scalable quantum computing.

Findings

Suppressed state-dependent force effects with single-ion experiments

Achieved a gate error of approximately 3.7e-4 in benchmarking

Predicted low crosstalk errors (~1e-5) for 17-qubit ion crystals

Abstract

A leading approach to implementing small-scale quantum computers has been to use laser beams, focused to micron spot sizes, to address and entangle trapped ions in a linear crystal. Here we propose a method to implement individually-addressed entangling gate interactions, but driven by microwave fields, with a spatial-resolution of a few microns, corresponding to $10^{-5}$ microwave wavelengths. We experimentally demonstrate the ability to suppress the effect of the state-dependent force using a single ion, and find the required interaction introduces $3.7(4)\times 10^{-4}$ error per emulated gate in a single-qubit benchmarking sequence. We model the scheme for a 17-qubit ion crystal, and find that any pair of ions should be addressable with an average crosstalk error of $\sim 10^{-5}$.