А как раз сегодня в arXiv'е вот такая толстая статья по квазиклассике в КЭД, с упором на рождение пар в сверхсильных полях, но исходные моменты точь-в-точь, как у меня:)) Но на меня не ссылаются, только на обзор и монографию великого и мудрого А.И. Ахиезера с моим любимым шефом...
WKB Electron Wave Functions in a Tightly Focused Laser Beam: https://arxiv.org/abs/2102.06692
A. Di Piazza
Available laser technology is opening the possibility of testing QED experimentally in the so-called strong-field regime. This calls for developing theoretical tools to investigate strong-field QED processes in electromagnetic fields of complex spacetime structure. Here, we propose a scheme to compute electron wave functions in tightly focused laser beams by taking into account exactly the complex spacetime structure of the fields. The scheme is solely based on the validity of the Wentzel-Kramers-Brillouin (WKB) approximation and the resulting wave functions, unlike previously proposed ones [Phys. Rev. Lett. \textbf{113}, 040402 (2014)], do not directly rely on approximations on the classical electron trajectory. Moreover, a consistent procedure is indicated to take into account higher-order quantum effects within the WKB approach depending on higher-and-higher powers of the Planck constant. In the case of a plane-wave background field we show that the found wave functions exactly reduce to the Volkov states, which are then written in a new and fully quasiclassical form. Finally, by using the leading-order WKB wave functions to compute the probabilities of nonlinear Compton scattering and nonlinear Breit-Wheeler pair production, it is explicitly shown that, if additionally the energies of the charges are sufficiently large that the latter are not significantly deflected by the field, the corresponding Baier's formulas are exactly reproduced for an otherwise arbitrary classical electron trajectory.
Comments: 49 pages, no figures
Апдейт: на следующий день - еще квазиклассика, но это уже несколько другое:
Electron-positron vacuum instability in strong electric fields. Relativistic semiclassical approach: https://arxiv.org/abs/2102.07182
D. N. Voskresensky
Instability of electron-positron vacuum in strong electric fields is studied. First, falling to the Coulomb center is discussed at Z>137/2 for a spinless boson and at Z>137 for electron. Then, focus is concentrated on description of deep electron levels and spontaneous positron production in the field of a finite-size nucleus with the charge Z>Zcr≃170. Next, these effects are studied in application to the low-energy heavy-ion collisions. Then, we consider phenomenon of "electron condensation" on levels of upper continuum crossed the boundary of the lower continuum ϵ=−m in the field of a supercharged nucleus with Z≫Zcr. Finally, attention is focused on many-particle problems of polarization of the QED vacuum and electron condensation at ultra-short distances from a source of charge. We argue for a principal difference of cases, when the size of the source is larger than the pole size rpole, at which the dielectric permittivity of the vacuum reaches zero, and smaller rpole. Some arguments are presented in favor of the logical consistency of QED. All problems are considered within the same relativistic semiclassical approach.
Comments: 56 pages, 6 figures