The binding energy of core electrons may not only provide information on the chemical composition, but also some additional information such as the type of bonding, which could be inferred from the shift of the binding energy, (also known as chemical shift). We present the study of the chemical shift using different theories, from Hartree-Fock and density-functional theory to many-body...
We investigate the properties of spin-imbalanced ultracold Fermi gas in a large range of spin polarizations at low temperatures. We present the results of microscopic calculations based on mean-field and density functional theory approaches, with no symmetry constraints. At low polarization values we predict the structure of the system as consisting of several spin-polarized droplets. As the...
X-ray photoelectron spectroscopy (XPS) measures electron removal (quasiparticle) energies, providing direct access to core and valence electron binding energies, hence probing the electronic structure. We present the benchmark of the ab initio many-body GW approximation on the complete electron binding energies of noble gas atoms (He-Rn), which spans 100 keV. Our results demonstrate that...
In this work, we calculate the ground state energy of pure neutron matter using the renormalization group based low-momentum effective interaction $V_{\text{low-}k}$ in Bogoliubov many-body perturbation theory (BMBPT), which is a perturbative expansion around the Hartree-Fock-Bogoliubov (HFB) ground state. In order to capture the low-density behavior of neutron matter, it turns out to be...
Supernova explosions, which will leave behind a neutron star, are the most powerful neutrino sources. The neutrino emission is also the dominating cooling mechanism for a (proto-)neutron star, whose interior is mainly composed of extremely dense and hot nuclear matter. Neutrinos can be scattered frequently inside stars before they escape. We study the neutrino scattering rates of neutron-star...
A quark-meson coupling model based on the quark model proposed by Bogoliubov for the description of the quark dynamics is developed and applied to the description of neutron stars. Starting from a SU(3) symmetry approach, it is shown that this symmetry has to be broken in order to satisfy the constraints set by the hypernuclei and by neutron stars. The model is able to describe observations...
Quantum computation is a relatively new field that seeks to harness the power of quantum mechanics to perform calculations that would be impossible with classical computers. The Schrödinger equation lies at the heart of quantum physics. In this poster, we present how to address the one-dimensional time evolution of wave-functions, as governed by the Schrödinger equation, on quantum computation...
We demonstrate the existence of a new type of spatially localized excitations in the unitary Fermi gas: spin polarized droplets with a peculiar internal structure involving the abrupt change of the pairing phase at the surface of the droplet. It resembles the structure of the Josephson-π junction occurring when a slice of a ferromagnet is sandwiched between two superconductors. The stability...
Landau’s Fermi liquid theory has provided a paradigmatic frame for the phenomenological description of equilibrium and transport properties of degenerate fermions in terms of very few characteristic parameters. Silin has set out the path to generalize for long-range forces, such to extend it for normal metals in condensed matter. Although the formal structure of the underlying microscopic...
Ab initio approaches to the nuclear many-body problem have seen their reach considerably extended over the last decade. However, collective excitations have seldom been addressed in that context, due to the prohibitive cost of solving the corresponding equations of motion.
We adapt a novel method originally proposed in the framework of the nuclear energy density functional method, and...
