Now showing items 21-30 of 30

  • Quantum versus mean-field collapse in a many-body system 

    Astrakharchik, Grigori; Malomed, Boris A. (2015-10-29)
    Article
    Open Access
    The recent analysis, based on the mean-field approximation (MFA), has predicted that the critical quantum collapse of the bosonic wave function, pulled to the center by the inverse-square potential in the three-dimensional ...
  • Reentrant behavior of the breathing-mode-oscillation frequency in a one-dimensional Bose gas 

    Gudyma, A; Astrakharchik, Grigori; Zvonarev, Mikhail (2015-08-07)
    Article
    Open Access
    Exciting temporal oscillations of the density distribution is a high-precision method for probing ultracold trapped atomic gases. Interaction effects in their many-body dynamics are particularly puzzling and counter-intuitive ...
  • Sharp crossover from composite fermionization to phase separation in microscopic mixtures of ultracold bosons 

    Garcia March, Miguel Angel; Julia Diaz, Bruno; Astrakharchik, Grigori; Busch, T; Boronat Medico, Jordi; Rios Polls, Artur (2013-12-03)
    Article
    Open Access
    We show that a two-component mixture of a few repulsively interacting ultracold atoms in a one-dimensional trap possesses very diverse quantum regimes and that the crossover between them can be induced by tuning the ...
  • Single-particle versus pair superfluidity in a bilayer system of dipolar bosons 

    Macia Rey, Adrián; Astrakharchik, Grigori; Mazzanti Castrillejo, Fernando Pablo; Giorgini, Stefano; Boronat Medico, Jordi (2014-10-21)
    Article
    Open Access
    We consider the ground state of a bilayer system of dipolar bosons, where dipoles are oriented by an external field in the direction perpendicular to the parallel planes. Quantum Monte Carlo methods are used to calculate ...
  • Spin dynamics and Andreev-Bashkin effect in mixtures of one-dimensional Bose gases 

    Parisi, L.; Astrakharchik, Grigori; Giorgini, Stefano (American Institute of Physics (AIP), 2018-07-11)
    Article
    Open Access
    We investigate the propagation of spin waves in two-component mixtures of one-dimensional Bose gases interacting through repulsive contact potentials. By using quantum Monte Carlo methods we calculate static ground-state ...
  • The inverse-square interaction phase diagram: unitarity in the bosonic ground state 

    Astrakharchik, Grigori; Kryuchkov, P. S.; Kurbakov, I. L.; Lozovik, Yu. E. (Multidisciplinary Digital Publishing Institute (MDPI), 2018-06-08)
    Article
    Open Access
    Ground-state properties of bosons interacting via inverse square potential (three dimensional Calogero-Sutherland model) are analyzed. A number of quantities scale with the density and can be naturally expressed in units ...
  • Thermodynamic behavior of a one-dimensional Bose gas at low temperature 

    de Rosi, Giulia; Astrakharchik, Grigori; Stringari, Sandro (AMER PHYSICAL SOC, 2017-07-11)
    Article
    Open Access
    We show that the chemical potential of a one-dimensional (1D) interacting Bose gas exhibits a nonmonotonic temperature dependence which is peculiar of superfluids. The effect is a direct consequence of the phononic nature ...
  • Ultradilute low-dimensional liquids 

    Petrov, D. S.; Astrakharchik, Grigori (2016-09-01)
    Article
    Open Access
    We calculate the energy of one- and two-dimensional weakly interacting Bose-Bose mixtures analytically in the Bogoliubov approximation and by using the diffusion Monte Carlo technique. We show that in the case of attractive ...
  • Universality in ultradilute liquid Bose-Bose mixtures 

    Cikojevic, V.; Vranješ Markic, Leandra; Astrakharchik, Grigori; Boronat Medico, Jordi (American Physical Society (APS), 2019-02-13)
    Article
    Open Access
    We have studied dilute Bose-Bose mixtures of atoms with attractive interspecies and repulsive intraspecies interactions using quantum Monte Carlo methods at T=0. Using a number of models for interactions, we determine the ...
  • Zero-temperature phase diagram of Yukawa bosons 

    Osychenko, O.N.; Astrakharchik, Grigori; Mazzanti Castrillejo, Fernando Pablo; Boronat Medico, Jordi (2012)
    Article
    Open Access
    We study the zero-temperature phase diagram of bosons interacting via screened Coulomb (Yukawa) potential by means of the diffusion Monte Carlo method. The Yukawa potential is used as a model interaction in the neutron ...