The Effect of Micromotion and Local Stress in Quantum simulation with Trapped Ions in Optical Tweezers

TL;DR

This paper investigates how optical tweezers can be used to control interactions in trapped ion quantum simulators, demonstrating robustness against micromotion and imperfections, with the need for precise intensity stabilization.

Contribution

It shows that optical tweezers effectively control ion interactions despite experimental imperfections, and that local stress offers negligible additional tuning.

Findings

Micromotion effects can be mitigated through optimized tweezer patterns.

Local stress has minimal impact on interaction tuning.

Intensity noise must be stabilized below 1% for reliable control.

Abstract

The ability to program and control interactions provides the key to implementing large-scale quantum simulation and computation in trapped ion systems. Adding optical tweezers, which can tune the phonon spectrum and thus modify the phonon-mediated spin-spin interaction, was recently proposed as a way of programming quantum simulators for a broader range of spin models [Arias Espinoza et al., Phys. Rev. A {\bf 103}, 052437]. In this work we study the robustness of our findings in the presence of experimental imperfections: micromotion, local stress, and intensity noise. We show that the effects of micromotion can be easily circumvented when designing and optimizing tweezer patterns to generate a target interaction. Furthermore, while local stress, whereby the tweezers apply small forces on individual ions, may appear to enable further tuning of the spin-spin interactions, any additional flexibility is negligible. We conclude that optical tweezers are a useful method for controlling interactions in trapped ion quantum simulators in the presence of micromotion and imperfections in the tweezer alignment, but require intensity stabilization on the sub-percent level.