469 / 2019-03-16 10:23:52

Alpha decay in intense laser fields

Intense laser; Alpha decay; Modification of penetrability

全体主题 > Fundamental Physics at Extremes

The past few decades witness rapid advancements in intense laser technologies. The chirped pulse amplification technique enables table-top Ti:sapphire lasers to have intensities exceeding one atomic unit (3.5×1016 W/cm2). Even higher intensities can be achieved by larger laser systems of different kinds, for example, the under-constructing extreme light infrastructure (ELI) of Europe is designed to reach peak intensities above 1023 W/cm2.
Widely accepted as a quantum tunneling process, alpha decay is expected to be modified in the presence of a strong laser field through modifying the potential barrier. In this talk we will discuss the effect of intense laser fields on nuclear alpha decay quantitatively. Our numerical results show that alpha decay can indeed be modified by strong external laser fields. For example, with a laser intensity of 1024 W/cm2, a modification of 0.1% to the alpha particle penetrability or the nuclear half life is predicted. A somewhat surprising result is that alpha decays with lower decay energies are relatively easier to be modified by external laser fields. Also, angle-resolved alpha penetrability is shown to be a first-order process, depending linearly on the laser field strength, whereas angle-integrated alpha penetrability is shown to be a second-order process, depending quadratically on the laser field strength, or linearly on the laser field intensity.