# Multi-ion sensing of dipolar noise sources in ion traps

## TL;DR

This paper introduces a method using two-ion probes to analyze electric-field noise sources in ion traps, providing insights into the microscopic mechanisms behind anomalous heating.

## Contribution

It presents a novel approach to determine dipole orientations and correlations, enabling testing of microscopic models of surface noise in ion traps.

## Key findings

- Demonstrates a transition in dissipation properties of two-ion probes
- Provides a way to measure dipole orientation and correlation length
- Proposes an experimentally feasible method with current technology

## Abstract

Trapped-ion quantum platforms are subject to `anomalous' heating due to interactions with electric-field noise sources of nature not yet completely known. There is ample experimental evidence that this noise originates at the surfaces of the trap electrodes, and models assuming fluctuating point-like dipoles are consistent with observations, but the exact microscopic mechanisms behind anomalous heating remain undetermined. Here we show how a two-ion probe displays a transition in its dissipation properties, enabling experimental access to the mean orientation of the dipoles and the spatial extent of dipole-dipole correlations. This information can be used to test the validity of candidate microscopic models, which predict correlation lengths spanning several orders of mag- nitude. Furthermore, we propose an experiment to measure these effects with currently-available traps and techniques.