First observation with global network of optical atomic clocks aimed for a dark matter detection

TL;DR

This paper presents the first global network of optical atomic clocks used as a quantum sensor for dark matter detection, achieving significant improvements in constraints on dark matter interactions with standard model particles.

Contribution

It introduces a novel earth-scale optical atomic clock network for dark matter searches, enabling sensitive detection without real-time clock comparisons and setting new constraints on dark matter interactions.

Findings

Two orders of magnitude improvement in constraints on transient variations of the fine-structure constant.

No dark matter signals detected, leading to tighter bounds on dark matter-SM couplings.

Successful deployment of optical atomic clocks across four labs on three continents.

Abstract

We report on the first earth-scale quantum sensor network based on optical atomic clocks aimed at dark matter (DM) detection. Exploiting differences in the susceptibilities to the fine-structure constant of essential parts of an optical atomic clock, i.e. the cold atoms and the optical reference cavity, we can perform sensitive searches for dark matter signatures without the need of real-time comparisons of the clocks. We report a two orders of magnitude improvement in constraints on transient variations of the fine-structure constant, which considerably improves the detection limit for the standard model (SM) - DM coupling. We use Yb and Sr optical atomic clocks at four laboratories on three continents to search for both topological defect (TD) and massive scalar field candidates. No signal consistent with a dark-matter coupling is identified, leading to significantly improved constraints on the DM-SM couplings.