Individual-Ion Addressing with Microwave Field Gradients

TL;DR

This paper demonstrates individual ion addressing in a trapped-ion quantum computer using microwave field gradients, achieving precise control with minimal crosstalk between ions separated by a few micrometers.

Contribution

It introduces four methods for hyperfine qubit control with microwave near-fields and experimentally demonstrates individual control with low crosstalk on two ions.

Findings

Achieved individual control on two ions separated by 4.3 micrometers.

Measured spin-flip crosstalk errors around 10^(-3).

Presented four approaches for hyperfine qubit manipulation.

Abstract

Individual-qubit addressing is a prerequisite for many instances of quantum information processing. We demonstrate this capability on trapped-ion qubits with microwave near-fields delivered by electrode structures integrated into a microfabricated surface-electrode trap. We describe four approaches that may be used in quantum information experiments with hyperfine levels as qubits. We implement individual control on two 25Mg+ ions separated by 4.3 micrometer and find spin-flip crosstalk errors on the order of 10^(-3).