Prospects for studying vacuum polarisation using dipole and synchrotron radiation

Understand

The measurement of vacuum polarisation effects, in particular vacuum birefringence, using combined optical and x-ray laser pulses is now actively pursued.

• Here we briefly examine the feasibility of two alternative setups.
• The first utilises an alternative target, namely a converging dipole pulse, and the second uses an alternative probe, namely the synchrotron-like emission from highly energetic particles, themselves interacting with a laser pulse.
• The latter setup has been proposed for experiments at ELI-NP.