Experimental Seminar

Experiments in Strong-field QED

by David Reis (Stanford)

US/Pacific
Other Institutes

Other Institutes

Madrone Conference Room, SLAC
Description

The interaction of intense light with matter is known to produce interesting new phenomena well beyond linear-response.  For optical wavelengths, such nonlinearities are exploited both in the perturbative and non-perturbative regimes, whereby sub-cycle tunnel ionization atoms lead to such phenomena as high-harmonic generation and above-threshold ionization.  For x rays, nonlinear interactions have only recently become accessible using free-electron lasers such as the LCLS.   At sufficiently high fields, even the vacuum becomes nonlinear.  Analogous to the atomic case, tunnel ionization of the vacuum into electron-positron pairs can occur at field strengths comparable to the electron mass in a Compton wavelength.  Such fields are orders of magnitude away from what is possible with even the most intense lasers, but are expected to occur in various astrophysical phenomena as well as in beam-beam collisions in future lepton colliders.  Importantly, they can also occur in the collisions of high energy electrons or photons with a strong laser field.  In this talk, I will discuss efforts to systematically explore this strong-field regime of QED, including at the FACET-II facility at SLAC.  I will describe what new phenomena we expect to see and how this differs qualitatively from perturbative QED, such as was studied two decades ago on the seminal SLAC E144 experiment. 

Organised by

Miriam Diamond