5 research outputs found
Alternative gauge for the description of the light-matter interaction in a relativistic framework
We present a generalized velocity gauge form of the relativistic laser-matter
interaction. In comparison with the (equivalent) regular minimal coupling
description, this new form of the light-matter interaction results in superior
convergence properties for the numerical solution of the time-dependent Dirac
equation. This applies both to the numerical treatment and, more importantly,
to the multipole expansion of the laser field. The advantages of the
alternative gauge is demonstrated in hydrogen by studies of the dynamics
following the impact of superintense laser pulses of extreme ultraviolet
wavelengths and sub-femtosecond duration