Single-Point Search for eV-scale Axion-like particles with Variable-Angle Three-Beam Stimulated Resonant Photon Collider

TL;DR

This paper introduces a novel laboratory method using a variable-angle three-beam stimulated resonant photon collider to search for axion-like particles in the eV mass range, setting new upper limits on their coupling strength.

Contribution

It presents the first model-independent upper limit on ALP-photon coupling at eV masses using a new collider technique that scans continuously across the energy range.

Findings

No excess signal observed at 2.27 eV mass.

Set a 95% confidence level upper limit on ALP-photon coupling.

Demonstrated feasibility of eV-scale mass scans in laboratory settings.

Abstract

We report a laboratory search for axion-like particles (ALPs) in the eV-mass range using a variable-angle three-beam stimulated resonant photon collider. The scheme independently focuses and collides three laser beams, providing a cosmology- and astrophysics-independent test. By varying the angles of incidence, the center-of-mass energy can be scanned continuously across the eV range. In this work, we operated the collider in a vacuum chamber at a large-angle configuration, verified the spacetime overlap of the three short pulses, and performed a first search centered at $m_a\simeq 2.27~\mathrm{eV}$. No excess was observed. We thus set a $95\%$ C.L.\ upper limit on the pseudoscalar two-photon coupling, with a minimum sensitivity of $g/M\simeq 4.2\times 10^{-10}~\mathrm{GeV}^{-1}$ at $m_a=2.27~\mathrm{eV}$. This provides the first model-independent upper limit on the coupling that reaches the KSVZ benchmark in the eV regime and demonstrates the feasibility of eV-scale mass scans in the near future.