Signatures of vacuum birefringence in low-power flying focus pulses

Journal Article · 07 March 2024 · Physical Review. D.

DOI: https://doi.org/10.1103/PhysRevD.109.056009 · OSTI ID:2320313

Formanek, Martin ; Palastro, John P. ; Ramsey, Dillon ; Weber, Stefan ; Di Piazza, Antonino

Vacuum birefringence produces a differential phase between orthogonally polarized components of a weak electromagnetic probe in the presence of a strong electromagnetic field. Despite representing a hallmark prediction of quantum electrodynamics, vacuum birefringence remains untested in pure light configurations due to the extremely large electromagnetic fields required for a detectable phase difference. Here, we exploit the programmable focal velocity and extended focal range of a flying focus laser pulse to substantially lower the laser power required for detection of vacuum birefringence. In the proposed scheme, a linearly polarized x-ray probe pulse counterpropagates with respect to a flying focus pulse, whose focus moves at the speed of light in the same direction as the x-ray probe. The peak intensity of the flying focus pulse overlaps the probe over millimeter-scale distances and induces a polarization ellipticity on the order of ${10}^{-10}$ , which lies within the detection sensitivity of existing x-ray polarimeters. Published by the American Physical Society 2024

• Sponsoring Organization: USDOE Office of Science (SC), Fusion Energy Sciences (FES); USDOE National Nuclear Security Administration (NNSA)
• Grant/Contract Number: NA0003856
• OSTI ID: 2320313
• Alternate ID(s): OSTI ID: 2323913; OSTI ID: 2376187
• Journal Information: Physical Review. D., Journal Name: Physical Review. D. Journal Issue: 5 Vol. 109; ISSN PRVDAQ; ISSN 2470-0010
• Publisher: American Physical SocietyCopyright Statement
• Country of Publication: United States
• Language: English