arXiv subjects

Geoffrey Stenuit

Publications and source records attributed to Geoffrey Stenuit.

3 recordsLinked to original sources

arXiv2008

Bridging the size gap between density-functional and many-body perturbation theory

The calculation of quasi-particle spectra based on the GW approximation is extended to systems of hundreds of atoms, thus expanding the size range of current approaches by more than one order of magnitude. This is achieved through an optimal strategy, based on the use of Wannier-like orbitals, for evaluating the polarization propagator. Our method is validated by calculating the vertical ionization energies of the benzene molecule and the band structure of crystalline silicon. Its potentials are then demonstrated by addressing the quasi-particle spectrum of a model structure of vitreous silica, as well as of the tetraphenylporphyrin molecule.

cond-mat.mtrl-sci↗

arXiv2000

On Electric Fields in Low Temperature Superconductors

The manifestly Lorentz covariant Landau-Ginzburg equations coupled to Maxwell's equations are considered as a possible framework for the effective description of the interactions between low temperature superconductors and magnetic as well as electric fields. A specific experimental set-up, involving a nanoscopic superconductor and only static applied fields whose geometry is crucial however, is described, which should allow to confirm or invalidate the covariant model through the determination of the temperature dependency of the critical magnetic-electric field phase diagram and the identification of some distinctive features it should display.

cond-mat.supr-con↗

arXiv1999

Annular Vortex Solutions to the Landau-Ginzburg Equations in Mesoscopic Superconductors

New vortex solutions to the Landau-Ginzburg equations are described. These configurations, which extend the well known Abrikosov and giant magnetic vortex ones, consist of a succession of ring-like supercurrent vortices organised in a concentric pattern, possibly bound to a giant magnetic vortex then lying at their center. The dynamical and thermodynamic stability of these annular vortices is an important open issue on which hinges the direct experimental observation of such configurations. Nevertheless, annular vortices should affect indirectly specific dynamic properties of mesoscopic superconducting devices amenable to physical observation.

cond-mat.supr-con↗