Light by Light Scattering as a New Probe for Axions

TL;DR

This paper proposes a novel method using resonance-enhanced vacuum birefringence during Light-by-Light scattering to detect axions in the 10^{-2} to 1 eV mass range, surpassing standard model backgrounds.

Contribution

It introduces a new detection scheme leveraging resonance effects in laser interactions to improve axion search sensitivity in high-intensity laser experiments.

Findings

Resonance at the axion mass enhances ellipticity signals.

The method can probe QCD axions in the 10^{-2} to 1 eV mass range.

Potential to discriminate axion signals from standard model backgrounds.

Abstract

We study the impact of virtual axions on the polarization of photons inside a cavity during the interaction of high-power laser pulses. A novel detection scheme for measuring the axion-induced ellipticity signal during the Light-by-Light (LBL) scattering process is investigated. We show that a momentum exchange between photons in a probe laser beam and a high-intensity target beam may lead to a resonance at the physical mass of the axion. Consequently, the resonant enhancement of vacuum birefringence gives rise to a large ellipticity signal. This signal enhancement can be applied in order to discriminate between the axion contribution to LBL scattering and the standard model contribution due to electron-positron pairs. The sensitivity of the scheme is studied for experimentally feasible probe light sources and ultrahigh intensity laser backgrounds. It is shown that this technique has the potential to probe the QCD axion in the mass range $10^{-2} \textrm{eV} \lesssim m_{a} \lesssim 1 \textrm{eV}$. In this region the axion induced signal surpasses the standard model background.