2019/08/31 by Scott Robertson · 23 citations
Physics and Astronomy · #Axion #Dark Matter and Cosmic Phenomena #Laser #Linear polarization #Particle physics #Photon #Photon polarization #Physics #Polarization (electrochemistry) #Quantum Electrodynamics and Casimir Effect #Quantum electrodynamics #Quantum mechanics #Quantum optics and atomic interactions #Vacuum energy #Vacuum polarization #physics.optics
paper · pdf · doi:10.1103/physreva.100.063831
published in Physical Review A 100(6) (American Physical Society) · 20 pages, 2 figures. Accepted for publication in Phys. Rev. A
arxiv created 2019/12/16 · openalex publication_date 2019/12/18 · arxiv updated 2019/12/25 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/06
From an effective field theory of electromagnetism in vacuum including all lowest-order nonlinear terms consistent with Lorentz invariance and locality of photon-photon interactions, we derive an effective-medium description of strong background fields as regards their influence on a weak probe. We mainly consider as background a pump beam with well-defined wave vector and polarization. This leads us to define a nonlinear index of vacuum which, in the Euler-Heisenberg model derived from QED, has an optimal value of 1.555\ifmmode×\else\texttimes\fi10^\ensuremath-33\phantom\rule0.28em0excm2/W for a linearly polarized pump as seen by a counterpropagating, orthogonally polarized probe. We further generalize the model to include coupling to an axion field. In the limit where the axion mass is much smaller than the typical photon energy, this yields dispersive corrections, and the axionic signature is found to be greatly enhanced for a circularly polarized pump as compared to a linearly polarized one. The formalism here presented points to a simplification of the DeLLight experiment [Sarazin et al., Eur. Phys. J. D 70, 13 (2016)] aiming to measure the deflection of a probe by a tightly focused laser pulse.