# Constraining Rapidly Oscillating Scalar Dark Matter Using Dynamic Decoupling

## TL;DR

This paper introduces an experimental method using Dynamic Decoupling to detect light scalar Dark Matter by observing oscillations in fundamental constants, providing new bounds on DM models at MHz frequencies.

## Contribution

The paper presents a novel application of Dynamic Decoupling in atomic systems to set model-independent bounds on light scalar DM, including relaxion and boson star scenarios.

## Key findings

- Established bounds on variations of fundamental constants up to MHz frequencies.
- Demonstrated the feasibility of using DD for DM detection in a tabletop experiment.
- Showed potential for the method to complement gravitational probes of scalar DM.

## Abstract

We propose and experimentally demonstrate a method for detection of light scalar Dark Matter (DM), through probing temporal oscillations of fundamental constants in an atomic optical transition. Utilizing the quantum information notion of Dynamic Decoupling (DD) in a table-top setting, we are able to obtain model-independent bounds on variations of $\alpha$ and $m_e$ at frequencies up to the MHz scale. We interpret our results to constrain the parameter space of light scalar DM field models. We consider the generic case, where the couplings of the DM field to the photon and to the electron are independent, as well as the case of a relaxion DM model, including the scenario of a DM boson star centered around Earth. Given the particular nature of DD, allowing to directly observe the oscillatory behaviour of coherent DM, and considering future experimental improvements, we conclude that our proposed method could be complimentary to, and possibly competitive with, gravitational probes of light scalar DM.