• Absorbers as detectors for unbound quantum systems 

      Selstø, Sølve (Physical Review A (PRA);Vol. 106, Iss. 4, Peer reviewed; Journal article, 2022-10-19)
      Complex absorbing potentials are frequently employed in quantum calculations. One of the advantages that such absorbers provide is the ability to attenuate outgoing waves in simulations of unbound systems, thus allowing ...
    • 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 ...
    • Distinction between sequential and direct ionization in two-photon double ionization of helium 

      Selstø, Sølve (Physical Review A. Atomic, Molecular, and Optical Physics;90, Journal article; Peer reviewed, 2014-11-10)
      This paper aims to shed some light on the role of the direct, or nonsequential, ionization channel in the regime in which the sequential channel is open in two-photon double ionization (TPDI) of helium. In this regime the ...
    • Formulae for partial widths derived from the Lindblad equation 

      Selstø, Sølve (Journal article; Peer reviewed; Journal article, 2012-06-28)
      A method for calculating partial widths of autoionizing states is proposed. It combines either a complex absorbing potential or exterior complex scaling with the Lindblad equation. The corresponding classical rate equations ...
    • 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 ...
    • Relativistic photoionization with elliptically polarized laser fields in the ultraviolet region 

      Kjellsson Lindblom, Tor Hugo Iwao; Selstø, Sølve (Physical Review A (PRA);104, 043102, Peer reviewed; Journal article, 2021-10-04)
      An alternative and powerful Schrödinger-like equation for describing beyond dipole laser-matter interactions is derived. It is shown that this particular formulation is numerically very efficient with respect to computational ...
    • Scattering in a quantum dot: the role of resonances 

      Selstø, Sølve (Journal of Physics: Condensed Matter;25(31), Journal article; Peer reviewed, 2013-07-09)
      The dynamics of a system in which an electron is incident on a populated quantum dot is studied by resolving the time dependence of the system. Specifically, one electron is initially at rest in the ground state of the ...
    • Schrödinger formulation of the nondipole light-matter interaction consistent with relativity 

      Førre, Morten; Selstø, Sølve (Physical Review A (PRA);Vol. 101, Iss. 6 — June 2020, Journal article; Peer reviewed, 2020-06-25)
      An alternative and powerful Schrödinger-like equation for describing beyond dipole laser-matter interactions and leading relativistic corrections is derived. It is shown that this particular formulation is numerically very ...
    • 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 ...
    • What do quantum computing students need to know about quantum physics? 

      Bungum, Berit; Selstø, Sølve (Peer reviewed; Journal article, 2022)
      Quantum computing is a rapidly developing technology, and we are experiencing an urgent need for experts in the field. However, there is a lack of traditions, research, and development on to what extent, and how, information ...