Topological transitions of the Fermi surface of osmium under pressure: an LDA+DMFT study

The influence of pressure on the electronic structure of Os has attracted substantial attention recently due to reports on isostructural electronic transitions in this metal. Here, we theoretically investigate the Fermi surface of Os from ambient to high pressure, using density functional theory combined with dynamical mean field theory. We provide a detailed discussion of the calculated Fermi surface and its dependence on the level of theory used for the treatment of the electron–electron interactions. Although we confirm that Os can be classified as weakly correlated metal, the inclusion of local quantum fluctuations between $5{\rm{d}}$ electrons beyond the local density approximation explains the most recent experimental reports regarding the occurrence of electronic topological transitions in Os.