High-fidelity local addressing of trapped ions and atoms by composite sequences of laser pulses

TL;DR

This paper introduces a composite laser pulse sequence method for high-fidelity, localized addressing of qubits in atomic or ionic lattices, improving precision and robustness beyond traditional diffraction limits.

Contribution

It presents novel high-fidelity composite pulses for single-qubit operations that enable precise local addressing within closely spaced atomic or ionic arrays.

Findings

Reduces addressing errors significantly

Enhances robustness of qubit manipulations

Potential to beat the diffraction limit

Abstract

A vital requirement for a quantum computer is the ability to locally address, with high fidelity, any of its qubits without affecting their neighbors. We propose an addressing method using composite sequences of laser pulses, which reduces dramatically the addressing error in a lattice of closely spaced atoms or ions, and at the same time significantly enhances the robustness of qubit manipulations. To this end, we design novel high-fidelity composite pulses for the most important single-qubit operations. In principle, this method allows one to beat the diffraction limit, for only atoms situated in a small spatial region around the center of the laser beam are excited, well within the laser beam waist.