• Alternative gauge for the description of the light-matter interaction in a relativistic framework 

      Selstø, Sølve; Kjellsson, Tor; Lindroth, Eva; Simonsen, Aleksander; Førre, Morten (Journal article; Peer reviewed, 2017)
      We present a generalized velocity gauge form of the relativistic laser-matter interaction. In comparison with the (equivalent) regular minimal coupling description, this form of light-matter interaction results in ...
    • Ionization dynamics beyond the dipole approximation induced by the pulse envelope 

      Simonsen, Aleksander; Kjellsson, Tor; Førre, Morten; Lindroth, Eva; Selstø, Sølve (Peer reviewed; Journal article, 2016-05-16)
      When atoms and molecules are ionized by laser pulses of finite duration and increasingly high intensities, the validity of the much-used dipole approximation, in which the spatial dependence and magnetic component of the ...
    • Relativistic dynamics for hydrogenlike systems 

      Kjellsson, Tor; Selstø, Sølve; Bræck, Simen; Lindroth, Eva (Peer reviewed; Journal article, 2015)
      The interaction between super intense laser pulses and hydrogenlike systems is investigated. We aim to study cases where the field drives the electron up to velocities of v~0.5c, where relativistic effects are believed to ...
    • Relativistic effects in photoionizing a circular Rydberg state in the optical regime 

      Kjellsson Lindblom, Tor Hugo Iwao; Lindroth, Eva; Førre, Morten; Selstø, Sølve (Physical Review A (PRA);102, 063108 (2020), Journal article; Peer reviewed, 2020-12-11)
      We study the photoionization process of a hydrogen atom initially prepared in a circular Rydberg state. The atom is exposed to a two-cycle laser pulse with a central wavelength of 800 nm. Before the atom approaches saturation, ...
    • Relativistic ionization dynamics for a hydrogen atom exposed to superintense XUV laser pulses 

      Kjellsson, Tor; Selstø, Sølve; Lindroth, Eva (Journal article; Peer reviewed, 2017)
      We present a theoretical study of the ionization dynamics of a hydrogen atom exposed to attosecond laser pulses in the extreme ultraviolet region at very high intensities. The pulses are such that the electron is expected ...
    • Semirelativistic Schrödinger Equation for Relativistic Laser-Matter Interactions 

      Kjellsson Lindblom, Tor; Førre, Morten; Lindroth, Eva; Selstø, Sølve (Physical Review Letters;Vol. 121, Iss. 25 — 21 December 2018, Journal article; Peer reviewed, 2018)
      A semirelativistic formulation of light-matter interaction is derived using the so called propagation gauge and the relativistic mass shift. We show that relativistic effects induced by a superintense laser field can, to ...
    • Solution of the Dirac equation for hydrogenlike systems exposed to intense electromagnetic pulses 

      Selstø, Sølve; Bengtsson, Jakob; Lindroth, Eva (Journal article; Peer reviewed, 2009)
      The time-dependent Dirac equation is solved numerically and compared to the corresponding prediction of the nonrelativistic Schrödinger equation for hydrogenlike systems exposed to intense laser pulses. It is found that ...
    • Solution of the time-dependent Schrödinger equation using uniform complex scaling 

      Bengtsson, Jakob; Lindroth, Eva; Selstø, Sølve (Journal article; Journal article; Peer reviewed, 2008)
      The formalism of complex rotation of the radial coordinate is studied in the context of time-dependent systems. The applicability of this method is discussed and illustrated with numerical examples involving atoms exposed ...
    • The structure behind it all 

      Lindroth, Eva; Argenti, Luca; Bengtsson, Jakob; Ferro, Fabrizio; Genkin, Michael; Selstø, Sølve (Journal article; Peer reviewed; Journal article, 2009)
      The talk discussed collisions where the structure of the systems involved plays a decisive role for the outcome of the event. For many types of charge changing processes the presence of resonant states can change the ...
    • Wave functions associated with time-dependent, complex-scaled Hamiltonians evaluated on a complex time grid 

      Bengtsson, Jakob; Lindroth, Eva; Selstø, Sølve (Journal article; Peer reviewed, 2012-01-30)
      We solve the time-dependent Schrödinger equation with themethod of uniform complex scaling and investigate the possibility to evaluate the solution on a complex time grid. With this approach it is possible to calculate ...