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Related papers: Pairing Matrix Elements and Pairing Gaps with Bare…

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We study pairing in low-density neutron matter including the screening interaction due to the exchange of particle-hole and RPA excitations. As bare force we employ the effective low-momentum interaction $V_{low\,k}$, while the Fermi-liquid…

Nuclear Theory · Physics 2018-08-23 S. Ramanan , M. Urban

We use the Negele-Vautherin density matrix expansion to derive a quasi-local density functional for the description of systems of fermions interacting with short-ranged interactions composed of arbitrary finite-range central, spin-orbit,…

Nuclear Theory · Physics 2010-07-21 J. Dobaczewski , B. G. Carlsson , M. Kortelainen

The induced pairing interaction arising from the exchange of collective surface vibrations among nucleons moving in time reversal states close to the Fermi energy is found to lead to values of the pairing gap which are similar to those…

Nuclear Theory · Physics 2007-05-23 F. Barranco , R. A. Broglia , G. Gori , E. Vigezzi , P. F. Bortignon , J. Terasaki

We study fermionic pairing in an ultracold two-component gas of $^6$Li atoms by observing an energy gap in the radio-frequency excitation spectra. With control of the two-body interactions via a Feshbach resonance we demonstrate the…

Superconductivity · Physics 2007-05-23 C. Chin , M. Bartenstein A. Altmeyer , S. Riedl , S. Jochim , J. Hecker Denschlag , R. Grimm

Motivated by recent advances in the creation of few-body atomic Fermi gases with attractive interactions, we study theoretically the few-to-many-particle crossover of pair excitations, which for large particle numbers evolve into a mode…

Quantum Gases · Physics 2024-12-04 Fabian Resare , Johannes Hofmann

The first detailed comparison of the low-momentum interaction V_{low k} with G matrices is presented. We use overlaps to measure quantitatively the similarity of shell-model matrix elements for different cutoffs and oscillator frequencies.…

Nuclear Theory · Physics 2009-11-11 A. Schwenk , A. P. Zuker

We use the induced interaction of Babu and Brown to derive two novel relations between the quasiparticle interaction in nuclear matter and the unique low momentum nucleon-nucleon interaction V_low k in vacuum. These relations provide two…

Nuclear Theory · Physics 2009-11-07 A. Schwenk , G. E. Brown , B. Friman

We report results of the equation of state of neutron matter in the low--density regime, where the Fermi wave vector ranges from $0.4 fm^{-1} \leq k_F \leq 1.0 fm^{-1}$. Neutron matter in this regime is superfluid because of the strong and…

Nuclear Theory · Physics 2009-10-29 S. Gandolfi , A. Yu. Illarionov , F. Pederiva , K. E. Schmidt , S. Fantoni

Based on a recent chiral approach to nuclear matter we calculate the in-medium interaction of nucleons at the Fermi surface $|\vec p_{1,2}|=k_f$. The isotropic part of this quasi-particle interaction is characterized by four density…

Nuclear Theory · Physics 2008-11-26 N. Kaiser

Quantum states of a two-component Fermi trapped gas are described by introducing an effective trap frequency, determined via variational techniques. Closed expressions for the contribution of a contact interaction potential to the total…

Other Condensed Matter · Physics 2009-11-10 R. Jáuregui , R. Paredes , G. Toledo Sánchez

We present the first applications of the second random-phase-approximation model with the finite-range Gogny interaction. We discuss the advantages of using such an interaction in this type of calculations where 2 particle-2 hole…

Nuclear Theory · Physics 2015-06-05 D. Gambacurta , M. Grasso , V. De Donno , G. Co' , F. Catara

This work aims at a global assessment of the effect of the density dependence of the zero-range pairing interaction. Systematic Skyrme-Hartree-Fock-Bogoliubov calculations with the volume, surface and mixed pairing forces are carried out to…

Nuclear Theory · Physics 2015-08-11 S. A. Changizi , Chong Qi

We extend density-matrix expansions in nuclei to higher orders in derivatives of densities and test their convergence properties. The expansions allow for converting the interaction energies characteristic to finite- and short-range nuclear…

Nuclear Theory · Physics 2011-04-19 B. G. Carlsson , J. Dobaczewski

In this work we theoretically study pairing in two-dimensional Fermi gases, a system which is experimentally accessible using cold atoms. We start by deriving the mean-field pairing gap equation for a coordinate-space potential with a…

Quantum Gases · Physics 2020-03-04 Tash Zielinski , Bernard Ross , Alexandros Gezerlis

We perform systematic calculations of pairing gaps in semi-magic nuclei across the nuclear chart using the Energy Density Functional method and a {\it non-empirical} pairing functional derived, without further approximation, at lowest order…

Nuclear Theory · Physics 2010-11-02 T. Lesinski , T. Duguet , K. Bennaceur , J. Meyer

Ground state energies and superfluid gaps are calculated for degenerate Fermi systems interacting via long attractive scattering lengths such as cold atomic gases, neutron and nuclear matter. In the intermediate region of densities, where…

Condensed Matter · Physics 2009-10-31 H. Heiselberg

The single-particle potentials for nucleons and hyperons in neutron-rich matter generally depends on the density and isospin asymmetry of the medium as well as the momentum and isospin of the particle. It further depends on the temperature…

Nuclear Theory · Physics 2014-07-02 Lie-Wen Chen , Che Ming Ko , Bao-An Li , Chang Xu , Jun Xu

A dilute homogeneous 3D Fermi gas in the ground state is considered for the case of a repulsive pairwise interaction. The low-density (dilution) expansions for the kinetic and interaction energies of the system in question are calculated up…

Statistical Mechanics · Physics 2009-11-10 A. A. Shanenko

The density-dependent finite-range Gogny force has been used to derive the effective Hamiltonian for the shell-model calculations of nuclei. The density dependence simulates an equivalent three-body force, while the finite range gives a…

Nuclear Theory · Physics 2018-10-31 Weiguang Jiang , Baishan Hu , Zhonghao Sun , Furong Xu

We investigate the role the interweaving of surface vibrations and nucleon motion has on Cooper pair formation in spherical superfluid nuclei. A quantitative calculation of the state-dependent pairing gap requires to go beyond the…

Nuclear Theory · Physics 2009-11-06 J. Terasaki , F. Barranco , R. A. Broglia , E. Vigezzi , P. F. Bortignon