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Title: Ground-State Properties of Unitary Bosons: From Clusters to Matter

Abstract

The properties of cold Bose gases at unitarity have been extensively investigated in the last few years both theoretically and experimentally. In this paper we use a family of interactions tuned to two-body unitarity and very weak three-body binding to demonstrate the universal properties of both clusters and matter. We determine the universal properties of finite clusters up to 60 particles and, for the first time, explicitly demonstrate the saturation of energy and density with particle number and compare with bulk properties. At saturation in the bulk we determine the energy, density, two- and three-body contacts, and the condensate fraction. We find that uniform matter is more bound than three-body clusters by nearly 2 orders of magnitude, the two-body contact is very large in absolute terms, and yet the condensate fraction is also very large, greater than 90%. Finally, equilibrium properties of these systems may be experimentally accessible through rapid quenching of weakly interacting boson superfluids.

Authors:
 [1];  [1];  [2];  [3]
  1. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
  2. Univ. of Paris-Sud, Orsay (France). Inst. of Nuclear Physics; Univ. of Arizona, Tucson, AZ (United States). Dept. of Physics
  3. Univ. of Campinas (Brazil). Inst. of Physics Gleb Wataghin
Publication Date:
Research Org.:
Univ. of Arizona, Tucson, AZ (United States); Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Univ. of Paris-Sud, Orsay (France)
Sponsoring Org.:
USDOE Office of Science (SC), Nuclear Physics (NP) (SC-26); USDOE Office of Science (SC), Advanced Scientific Computing Research (ASCR) (SC-21); European Union (EU)
OSTI Identifier:
1415405
Report Number(s):
LA-UR-17-25071
Journal ID: ISSN 0031-9007
Grant/Contract Number:
AC52-06NA25396; AC02-05CH11231; FG02-04ER41338; 654002
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Physical Review Letters
Additional Journal Information:
Journal Volume: 119; Journal Issue: 22; Journal ID: ISSN 0031-9007
Publisher:
American Physical Society (APS)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; atomic & molecular clusters; Bose gases; condensed matter & materials physics; atomic, molecular & optical

Citation Formats

Carlson, J., Gandolfi, S., van Kolck, U., and Vitiello, S. A. Ground-State Properties of Unitary Bosons: From Clusters to Matter. United States: N. p., 2017. Web. doi:10.1103/PhysRevLett.119.223002.
Carlson, J., Gandolfi, S., van Kolck, U., & Vitiello, S. A. Ground-State Properties of Unitary Bosons: From Clusters to Matter. United States. doi:10.1103/PhysRevLett.119.223002.
Carlson, J., Gandolfi, S., van Kolck, U., and Vitiello, S. A. 2017. "Ground-State Properties of Unitary Bosons: From Clusters to Matter". United States. doi:10.1103/PhysRevLett.119.223002.
@article{osti_1415405,
title = {Ground-State Properties of Unitary Bosons: From Clusters to Matter},
author = {Carlson, J. and Gandolfi, S. and van Kolck, U. and Vitiello, S. A.},
abstractNote = {The properties of cold Bose gases at unitarity have been extensively investigated in the last few years both theoretically and experimentally. In this paper we use a family of interactions tuned to two-body unitarity and very weak three-body binding to demonstrate the universal properties of both clusters and matter. We determine the universal properties of finite clusters up to 60 particles and, for the first time, explicitly demonstrate the saturation of energy and density with particle number and compare with bulk properties. At saturation in the bulk we determine the energy, density, two- and three-body contacts, and the condensate fraction. We find that uniform matter is more bound than three-body clusters by nearly 2 orders of magnitude, the two-body contact is very large in absolute terms, and yet the condensate fraction is also very large, greater than 90%. Finally, equilibrium properties of these systems may be experimentally accessible through rapid quenching of weakly interacting boson superfluids.},
doi = {10.1103/PhysRevLett.119.223002},
journal = {Physical Review Letters},
number = 22,
volume = 119,
place = {United States},
year = 2017,
month =
}

Journal Article:
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  • A formulation is given to derive an effective interaction in the framework of the unitary-model-operator approach. A unitary transformation is introduced to describe two-body correlations and is determined from the condition that the effective interaction should be decoupled between the low- and high-momentum spaces. A unitary transformation of the Hamiltonian is made and the transformed Hamiltonian is represented in a cluster-expansion form. The effective interaction thus defined is E independent and Hermitian. The contributions of one-, two-, and three-body-cluster terms are taken into consideration. The self-consistent single-particle potential is considered sym- metrically for both occupied (hole) and unoccupied (particle) states.more » The theory is applied to the calculation of the ground-state properties of /sup 16/O using three potentials, namely, the Paris, Reid soft-core, and supersoft-core potentials. A large gain in the binding energy is obtained. Final results for the gound-state energy and the charge radius are as follows: -119.2 MeV and 2.62 fm for the Paris, -115.1 MeV and 2.60 fm for the Reid soft core, and -121.7 MeV and 2.62 fm for the supersoft core. The single-particle energies of the occupied orbits are also calculated. Good agreement between the calculated and experimental energies is obtained. In particular, a large spin-orbit splitting of the 0p orbits is reproduced with the results 5.6 MeV for the Paris, 5.1 MeV for the Reid soft core, and 5.4 MeV for the supersoft core, which should be compared with the experimental value 6.1 MeV.« less
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  • We study the ground-state properties of hard-core bosons trapped by arbitrary confining potentials on one-dimensional optical lattices. A recently developed exact approach based on the Jordan-Wigner transformation is used. We analyze the large distance behavior of the one-particle density matrix, the momentum distribution function, and the lowest natural orbitals. In addition, the low-density limit in the lattice is studied systematically, and the results obtained compared with the ones known for the hard-core boson gas without the lattice.
  • We study properties of the strongly repulsive Bose gas on one-dimensional incommensurate optical lattices with a harmonic trap, which can be dealt with by use of an exact numerical method through Bose-Fermi mapping. We first exploit the phase transition of hard-core bosons in optical lattices from the superfluid to the Bose-glass phase as the strength of the incommensurate potential increases. Then we study the dynamical properties of the system after suddenly switching off the harmonic trap. We calculate the one-particle density matrices, the momentum distributions, and the natural orbitals and their occupations for both the static and dynamic systems. Ourmore » results indicate that the Bose-glass and superfluid phases display quite different properties and expansion dynamics.« less