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arXiv · 2605.08359

Probing the electromagnetic nonlinearity of vacuum with continuous-wave lasers

Alexey Arakcheev·Niv Barkai·Alexandr Vasilyev·Osip Schwartz
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Abstract

In classical electrodynamics, light waves propagating in vacuum do not interact. In quantum physics, however, photon-photon interactions are mediated by virtual particles, giving rise to the electromagnetic nonlinearity of vacuum (EMNV). A direct measurement of EMNV would test a long-standing prediction of quantum electrodynamics and constrain new physics models. Despite its fundamental significance and extensive efforts to detect it, free-space EMNV has not yet been directly measured in the laboratory. Here, we propose a tabletop all-optical measurement of EMNV based on resonantly enhanced four-wave mixing in focusing optical resonators with a circulating power of a few megawatts. As a key experimental step toward this measurement, we demonstrate a resonator reaching a circulating power of 2.5 MW, approaching the parameter range needed to detect EMNV at the level predicted by quantum electrodynamics.

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Alexey Arakcheev, Niv Barkai, Alexandr Vasilyev, Osip Schwartz. 2026-05-08. Probing the electromagnetic nonlinearity of vacuum with continuous-wave lasers. https://arxiv.org/abs/2605.08359

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