Towards generation of cat states in trapped ions set-ups via FAQUAD protocols and dynamical decoupling

TL;DR

This paper compares adiabatic and FAQUAD protocols for generating high-fidelity cat states in trapped ion systems, evaluating their robustness against dephasing and the effectiveness of dynamical decoupling techniques.

Contribution

It introduces a comparative analysis of Local Adiabatic and FAQUAD protocols with dynamical decoupling for entangled state generation in trapped ions.

Findings

FAQUAD protocols improve fidelity over traditional adiabatic methods.

Dynamical decoupling enhances robustness against dephasing effects.

Protocols are feasible with current experimental technology.

Abstract

The high fidelity generation of strongly entangled states of many particles, such as cat states, is a particularly demanding challenge. One approach is to drive the system, within a certain final time, as adiabatically as possible, in order to avoid the generation of unwanted excitations. However, excitations can be generated also by the presence of dissipative effects such as dephasing. Here we compare the effectiveness of Local Adiabatic and the FAst QUasi ADiabatic protocols in achieving a high fidelity for a target superposition state both with and without dephasing. In particular we consider trapped ions set-ups in which each spin interacts with all the others with the uniform coupling strength or with a power-law coupling. In order to mitigate the effects of dephasing, we complement the adiabatic protocols with dynamical decoupling and we test its effectiveness. The protocols we study could be readily implemented with state-of-the-art techniques.