Speaker
Description
Superradiance can cause the axion cloud around a rotating black hole to reach extremely high densities, and the decay of these axions can produce a powerful laser. The electric field of these lasers is strong enough that the Schwinger effect may become significant, resulting in the production of an electron-positron plasma. Here, I detail the dynamics between axion lasers and this electron-positron plasma. There are several mechanisms by which the inclusion of a plasma can impact the laser's behavior, the most significant being that the electron-positron plasma imparts an effective mass on the photon. As the plasma frequency increases, axion decay becomes energetically unfavorable, up to the point where the axion no longer decays into photons, shutting off the laser. The impact of the electron-positron plasma on the dynamics of the system depends heavily on the parameters, specifically the axion mass and the superradiant coupling. For certain parameters, the production of this electron-positron plasma prevents the system from ever reaching equilibrium, with the axion field continuing to grow while the laser luminosity remains constant.
