We present the dispersion relations for quasiparticle excitations about the color-flavor locked ground state of QCD at high baryon density. In the presence of condensates which pair light and strange quarks there need not be an energy gap in the quasiparticle spectrum. This raises the possibility of gapless color superconductivity, with a Meissner effect but no minimum excitation energy. Analys...

This talk is a status report on our study of quantum transport equations relevant for baryogenesis computations. Our main finding is that, as a consequence of localization in space, the quasiparticle picture of the plasma dynamics breaks down at first non-trivial order in gradient expansion. While in this talk we focus on bosons, we expect that a similar picture holds for fermions. We then argu...

The GW approximation [1] to many body perturbation theory represents the state of the art technique to calculate the quasiparticle correction to the band gap of solids and has been sucessfully applied to many materials. Although the GW approximation works well with pseudopotentials (PP’s) and plane wave basis sets used within Density Functional Theory Local density approximation (DFT-LDA), the ...

We study a superconducting charge qubit coupled to an intensive electromagnetic field and probe changes in the resonance frequency of the formed dressed states. At large driving strengths, exceeding the qubit energy-level splitting, this reveals the well known Landau-Zener-Stückelberg interference structure of a longitudinally driven two-level system. For even stronger drives, we observe a sign...

We present analytic expressions for the exact density functional and Kohn-Sham Hamiltonian of simple tight-binding models of correlated electrons. These are the singleand double-site versions of the Anderson, Hubbard, and spinless fermion models. The exact exchange and correlation potentials keep the full nonlocal dependence on electron occupations. The analytic expressions allow us to compare ...

Configuration-constrained potential-energy-surface calculations are performed including β6 deformation to investigate high-K isomeric states in nuclei around 254No and 270Ds, the heaviest nuclei where there have been some observations of two-quasiparticle isomers, while data for four-quasiparticle isomers are scarce. We predict the prevalent occurrence of four-quasiparticle isomeric states in t...

The carriers of electric current in a metal are quasiparticles dressed by electronelectron interactions, which have a larger effective mass m* and a smaller quasiparticle weight z than non-interacting carriers. If the momentum dependence of the self-energy can be neglected, the effective mass enhancement and quasiparticle weight of quasiparticles at the Fermi energy are simply related by z = m/...

We present an ab initio computational scheme for evaluating the dielectric response function of Si clusters. All calculations are carried out employing a basis of localized atomiclike orbitals and including quasiparticle corrections. The self-energy operator is evaluated in the GW approximation, with a full frequency dependence for the dielectric matrix. The approach is convenient and computati...

The problem of electron–electron lifetime in a quantum dot is studied beyond perturbation theory by mapping it onto the problem of localization in the Fock space. We identify two regimes, localized and delocalized, corresponding to quasiparticle spectral peaks of zero and finite width, respectively. In the localized regime, quasiparticle states are very close to single particle excitations. In ...