6 papers
Spin-Orbit Effects in Diluted Magnetic Semiconductors
Byounghak Lee, Xavier Cartoixa, Nandini Trivedi +1
We present a theoretical study of diluted magnetic semiconductors that treats the local sp-d exchange interaction J between the itinerant carriers and the Mn d electrons within a r…
First principles study of the Si(557)-Au surface
Daniel Sanchez-Portal, Richard M. Martin
We have performed a density functional study of fifteen different structural models of the Si(557)-Au surface reconstruction. Here we present a brief summary of the main structural…
Metallization of molecular hydrogen
Martin Staedele, Richard M. Martin
We study metallization of molecular hydrogen under pressure using exact exchange (EXX) Kohn-Sham density-functional theory in order to avoid well-known underestimates of band gaps…
Screening of a point charge: a fixed-node diffusion Monte Carlo study
Erik Koch, Olle Gunnarsson, Richard M. Martin
We study the static screening in a Hubbard-like model using fixed-node diffusion Monte Carlo. We find that the random phase approximation is surprisingly accurate even for metallic…
Fixed-node DMC for Fermions on a lattice: Application to the doped Fullerides
Erik Koch, Olle Gunnarsson, Richard M. Martin
Fullerides are crystals made from C60 molecules. When doped with alkali metals the valence electrons of the alkali atoms are transfered to the C60 molecules. We show how to set up…
Quantum Monte Carlo calculations for integer-doped Fullerides
Erik Koch, Olle Gunnarsson, Richard M. Martin
The doped Fullerides can be well described by a Hubbard model, which comprises the partly filled, threefold-degenerate t_1u orbital and the on-site Coulomb interaction U. The orbit…