Now showing items 1-20 of 36

    • Andreev-Bashkin effect in superfluid cold gases mixtures 

      Nespolo, Jacopo; Astrakharchik, Grigori; Recati, Alessio (2017-12-05)
      Article
      Open Access
      © 2017 The Author(s). Published by IOP Publishing Ltd on behalf of Deutsche Physikalische Gesellschaft. We study a mixture of two superfluids with density-density and current-current (Andreev-Bashkin) interspecies interactions. ...
    • Beyond-Luttinger-liquid thermodynamics of a one-dimensional Bose gas with repulsive contact interactions 

      Rosi, Giulia de; Massignan, Pietro Alberto; Lewenstein, Maciej; Astrakharchik, Grigori (American Physical Society, 2019-11-07)
      Article
      Open Access
      We present a thorough study of the thermodynamics of a one-dimensional repulsive Bose gas, focusing in particular on corrections beyond the Luttinger-liquid description. We compute the chemical potential, pressure, and ...
    • Bose polarons in ultracold atoms in one dimension: beyond the Fröhlich paradigm 

      Grusdt, Fabian; Astrakharchik, Grigori; Demler, Eugene (2017-10-25)
      Article
      Open Access
      Mobile impurity atoms immersed in Bose–Einstein condensates provide a new platform for exploring Bose polarons. Recent experimental advances in the field of ultracold atoms make it possible to realize such systems with ...
    • Coherent oscillations in small Fermi-polaron systems 

      Tylutki, Marek; Astrakharchik, Grigori; Recati, Alessio (AMER PHYSICAL SOC, 2017-12-01)
      Article
      Open Access
      We study the ground state and excitations of a one-dimensional trapped polarized Fermi gas interacting with a single impurity. First, we study the tunneling dynamics of the impurity through a potential barrier, such as one ...
    • Collective excitations of a one-dimensional quantum droplet 

      Tylutki, Marek; Astrakharchik, Grigori; Malomed, Boris A.; Petrov, D. S. (2020-05-21)
      Article
      Open Access
      We calculate the excitation spectrum of a one-dimensional self-bound quantum droplet in a two-component bosonic mixture described by the Gross-Pitaevskii equation (GPE) with cubic and quadratic nonlinearities. The cubic ...
    • Composite boson description of a low-density gas of excitons 

      Golomedov, A. E.; Lozovik, Yu. E.; Astrakharchik, Grigori; Boronat Medico, Jordi (2017-10-13)
      Article
      Open Access
      Ground-state properties of a fermionic Coulomb gas are calculated using the fixed-node diffusion Monte Carlo method. The validity of the composite boson description is tested for different densities. We extract the ...
    • Distinguishability, degeneracy, and correlations in three harmonically trapped bosons in one dimension 

      Garcia March, Miguel Angel; Julia Diaz, Bruno; Astrakharchik, Grigori; Boronat Medico, Jordi; Polls, A. (2014-12-01)
      Article
      Open Access
      We study a system of two bosons of one species and a third atom of a second species in a one-dimensional parabolic trap at zero temperature. We assume contact repulsive inter- and intraspecies interactions. By means of an ...
    • Dynamic structure function of a cold Fermi gas at unitarity 

      Astrakharchik, Grigori; Boronat Medico, Jordi; Krotscheck, Eckhard; Lichtenegger, Thomas (Institute of Physics (IOP), 2014-08-14)
      Article
      Open Access
      We present a theoretical study of the dynamic structure function of a resonantly interacting two-component Fermi gas at zero temperature. Our approach is based on dynamic many-body theory able to describe excitations in ...
    • Dynamics of one-dimensional quantum droplets 

      Astrakharchik, Grigori; Malomed, Boris A. (American Physical Society (APS), 2018-07-30)
      Article
      Open Access
      The structure and dynamics of one-dimensional binary Bose gases forming quantum droplets is studied by solving the corresponding amended Gross-Pitaevskii equation. Two physically different regimes are identified, corresponding ...
    • Exact ground-state properties of a one-dimensional Coulomb gas 

      Astrakharchik, Grigori; Girardeau, M.D. (2011-04-15)
      Article
      Open Access
      The ground-state properties of a single-component one-dimensional Coulomb gas are investigated. We use Bose-Fermi mapping for the ground-state wave function which permits solution of the Fermi sign problem in the following ...
    • Exact results for the boundary energy of one-dimensional bosons 

      Reichert, Benjamin; Astrakharchik, Grigori; Petkovic, Aleksandra; Ristivojevic, Zoran (American Institute of Physics (AIP), 2019-12-17)
      Article
      Open Access
      We study bosons in a one-dimensional hard-wall box potential. In the case of contact interaction, the system is exactly solvable by the Bethe ansatz, as first shown by Gaudin in 1971. Although contained in the exact solution, ...
    • Few-body bound states of two-dimensional bosons 

      Guijarro Gámez, Grecia; Astrakharchik, Grigori; Boronat Medico, Jordi; Bazak, Betzalel; Petrov, D. S. (American Physical Society (APS), 2020-04-07)
      Article
      Open Access
      We study clusters of the type $A_NB_M$ with N=M=3 in a two-dimensional mixture of A and B bosons, with attractive AB and equally repulsive AA and BB interactions. In order to check universal aspects of the problem, we ...
    • Gapped spectrum in pair-superfluid bosons 

      Astrakharchik, Grigori; Zillich, Robert E.; Mazzanti Castrillejo, Fernando Pablo; Boronat Medico, Jordi (2016-12-22)
      Article
      Open Access
      We study the ground state of a bilayer system of dipolar bosons with dipoles oriented by an external field perpendicularly to the two parallel planes. By decreasing the interlayer distance, for a fixed value of the strength ...
    • Liquid state of one-dimensional Bose mixtures: a quantum Monte Carlo study 

      Parisi, L.; Astrakharchik, Grigori; Giorgini, Stefano (American Institute of Physics (AIP), 2019-03-14)
      Article
      Open Access
      By using exact quantum Monte Carlo methods we calculate the ground-state properties of the liquid phase in one-dimensional Bose mixtures with contact interactions. We find that the liquid state can be formed if the ratio ...
    • Low-dimensional weakly interacting Bose gases: nonuniversal equations of state 

      Astrakharchik, Grigori; Boronat Medico, Jordi; Kurbakov, I L; Lozovik, Y E; Mazzanti Castrillejo, Fernando Pablo (2010-01)
      Article
      Open Access
      The zero-temperature equation of state is analyzed in low-dimensional bosonic systems. We propose to use the concept of energy-dependent s-wave scattering length for obtaining estimations of nonuniversal terms in the energy ...
    • Luttinger-liquid behavior of one-dimensional He-3 

      Astrakharchik, Grigori; Boronat Medico, Jordi (2014-12-30)
      Article
      Open Access
      The ground-state properties of one-dimensional He-3 are studied using quantum Monte Carlo methods. The equation of state is calculated in a wide range of physically relevant densities and is well interpolated by a power-series ...
    • One dimensional H-1, H-2 and H-3 

      Vidal, A.J.; Astrakharchik, Grigori; Vranješ Markic, Leandra; Boronat, J. (2016-05-26)
      Article
      Open Access
      The ground-state properties of one-dimensional electron-spin-polarized hydrogen H-1, deuterium H-2, and tritium 3 Hare obtained by means of quantum Monte Carlo methods. The equations of state of the three isotopes are ...
    • One-dimensional Bose gas in optical lattices of arbitrary strength 

      Astrakharchik, Grigori; Krutitsky, K.V.; Lewenstein, Maciej; Mazzanti Castrillejo, Fernando Pablo (2016-02-08)
      Article
      Open Access
      One-dimensional Bose gas with contact interaction in optical lattices at zero temperature is investigated by means of the exact diffusion Monte Carlo algorithm. The results obtained from the fundamental continuous model ...
    • One-dimensional multicomponent Fermi gas in a trap: quantum Monte Carlo study 

      Matveeva, N.; Astrakharchik, Grigori (2016-06-22)
      Article
      Open Access
      A one-dimensional world is very unusual as there is an interplay between quantum statistics and geometry, and a strong short-range repulsion between atoms mimics Fermi exclusion principle, fermionizing the system. Instead, ...
    • One-dimensional three-boson problem with two- and three-body interactions 

      Guijarro Gámez, Grecia; Pricoupenko, A.; Astrakharchik, Grigori; Boronat Medico, Jordi; Petrov, D. S. (American Physical Society (APS), 2018-06-14)
      Article
      Open Access
      We solve the three-boson problem with contact two- and three-body interactions in one dimension and analytically calculate the ground and excited trimer-state energies. Then, by using the diffusion Monte Carlo technique, ...