Sökning: "Viktor Christiansson"

Hittade 2 uppsatser innehållade orden Viktor Christiansson.

1. 1. The self-screening correction to RPA and GW – A model and ab initio study

   Master-uppsats, Lunds universitet/Matematisk fysik; Lunds universitet/Fysiska institutionen

   Författare :Viktor Christiansson; [2019]
   Nyckelord :GW approximation; GWA; Random-Phase-Approximation; RPA; Self-screening; Self-screening correction; Beyond RPA; Beyond GW; Physics and Astronomy;

   Sammanfattning : The self-screening error in the GW approximation is studied by applying correction schemes beyond the random-phase approximation in model and ab inito calculations. Two model systems in the form of Hubbard dimers, with one and two orbitals per site respectively, are considered. LÄS MER

3. 2. Model study of the linear density response function - A comparison between the exact result and RPA

   Kandidat-uppsats, Lunds universitet/Fysiska institutionen; Lunds universitet/Matematisk fysik

   Författare :Viktor Christiansson; [2017]
   Nyckelord :Physics and Astronomy;

   Sammanfattning : The time-ordered linear density response function is examined in a model study. Two model dimers are considered; one with one orbital per site and a second one with two orbitals per site. The one-orbital case has U0, the on-site Coulomb interaction, as the only parameter and is solved analytically. LÄS MER