Energetics and Structural Properties of Trapped Two-Component Fermi Gases

Abstract

Using two different numerical methods, we study the behavior of two-component Fermi gases interacting through short-range s-wave interactions in a harmonic trap. A correlated Gaussian basis-set expansion technique is used to determine the energies and structural properties, i.e., the radial one-body densities and pair distribution functions, for small systems with either even or odd $N$, as functions of the s-wave scattering length and the mass ratio $\kappa$ of the two species. Particular emphasis is put on a discussion of the angular momentum of the system in the BEC-BCS crossover regime. At unitarity, the excitation spectrum of the four-particle system with total angular momentum L=0 is calculated as a function of the mass ratio $\kappa$. The results are analyzed from a hyperspherical perspective, which offers new insights into the problem. Additionally, fixed-node diffusion Monte Carlo calculations are performed for equal-mass Fermi gases with up to N=30 atoms. We focus on the odd-even oscillations of the ground state energy of the equal-mass unitary system having up to N=30 particles, which are related to the excitation gap of the system. Furthermore, we present a detailed analysis of the structural properties of these systems.

22 pages, 21 figures

References in corpus (44)

• Pairing and Phase Separation in a Polarized Fermi Gas
• Observation of Bose-Einstein Condensation of Molecules
• Stable 85Rb Bose-Einstein Condensates with Widely Tunable Interactions
• Evidence for Superfluidity in a Resonantly Interacting Fermi Gas
• Fermionic atoms in a 3D optical lattice: Observing Fermi-surfaces, dynamics and interactions
• Weakly bound dimers of fermionic atoms
• Superfluid Fermi Gases with Large Scattering Length
• Conversion of an Atomic Fermi Gas to a Long-Lived Molecular Bose Gas
• Equation of state of a Fermi gas in the BEC-BCS crossover: a quantum Monte Carlo study
• Confinement induced molecules in a 1D Fermi gas
• Measurement of interaction energy near a Feshbach resonance in a 6Li Fermi gas
• Direct Observation of the Superfluid Phase Transition in Ultracold Fermi Gases
• Three-body problem in Fermi gases with short-range interparticle interaction
• Asymmetric Two-component Fermion Systems in Strong Coupling
• Free fermion antibunching in a degenerate atomic Fermi gas released from an optical lattice
• The unitary gas in an isotropic harmonic trap: symmetry properties and applications
• Quantum Monte Carlo Studies of Superfluid Fermi Gases
• Finite temperature phase diagram of a polarised Fermi condensate
• Self-consistent model of ultracold atomic collisions and Feshbach resonances in tight harmonic traps
• Virial Theorem and Universality in a Unitary Fermi Gas
• Long-lived Feshbach molecules in a 3D optical lattice
• The potential energy of a ${}^{40}$K Fermi gas in the BCS-BEC crossover
• Unbiased estimators in Quantum Monte Carlo methods: application to liquid ${}^4$He
• Local Density Functional Theory for Superfluid Fermionic Systems: The Unitary Gas
• Two-species fermion mixtures with population imbalance
• Low-energy three-body dynamics in binary quantum gases
• Scattering Length Scaling Laws for Ultracold Three-Body Collisions
• Universal properties of a trapped two-component Fermi gas at unitarity
• Diatomic molecules in ultracold Fermi gases - Novel composite bosons
• Mesoscopic Fermi gas in a harmonic trap
• Effective Theory for Trapped Few-Fermion Systems
• Unitary Fermi Gas in a Harmonic Trap
• Spectrum and Dynamics of the BCS-BEC crossover from a few-body perspective
• BEC-BCS Crossover of a Trapped Two-Component Fermi Gas with Unequal Masses
• Resonant pairing between Fermions with unequal masses
• Level crossing in the three-body problem for strongly interacting fermions in a harmonic trap
• Mixtures of ultracold fermions with unequal masses
• Superfluid shells for trapped fermions with mass and population imbalance
• Co-existence and shell structures of several superfluids in trapped three-component Fermi mixtures
• Correlated Trapped Bosons and the Many-Body Efimov Effect
• Ground State Properties of Fermi Gases in the Strongly Interacting Regime
• Hyperspherical Description of the Degenerate Fermi Gas: S-wave Interactions
• Renormalized mean-field theory for a two-component Fermi gas with s-wave interactions
• BEC-BCS crossover of a trapped Fermi gas without using the local density approximation

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• The BCS-BEC crossover: From ultra-cold Fermi gases to nuclear systems
• Applications of quantum Monte Carlo methods in condensed systems
• Few-body physics with ultracold atomic and molecular systems in traps
• General relations for quantum gases in two and three dimensions. Two-component fermions
• Comparing and contrasting nuclei and cold atomic gases
• Virial expansion for a strongly correlated Fermi system and its application to ultracold atomic Fermi gases
• Superfluid Bose-Fermi mixture from weak-coupling to unitarity
• Topological phases for bound states moving in a finite volume
• Virial theorems for trapped cold atoms
• Atom-dimer and dimer-dimer scattering in fermionic mixtures near a narrow Feshbach resonance
• Natural and unnatural parity states of small trapped equal-mass two-component Fermi gases at unitarity and fourth-order virial coefficient
• Self-trapping of a Fermi super-fluid in a double-well potential in the BEC-unitarity crossover
• Correlated Gaussian Hyperspherical Method for Few-Body Systems
• Breakdown of universality for unequal-mass Fermi gases with infinite scattering length
• Effective Nonlinear Schrödinger Equations for Cigar-Shaped and Disk-Shaped Fermi Superfluids at Unitarity
• Three and Four Harmonically Trapped Particles in an Effective Field Theory Framework
• Energy spectrum of harmonically trapped two-component Fermi gases: Three- and Four-Particle Problem
• The Hyperspherical Four-Fermion Problem
• Benchmark calculations for elastic fermion-dimer scattering
• Pairing of few Fermi atoms in one dimension
• Time-Dependent Density Functional Theory for Fermionic Superfluids: from Cold Atomic Gases, to Nuclei and Neutron Stars Crust
• Illustration of universal relations for trapped four-fermion system with arbitrary s-wave scattering length
• Probing strongly interacting atomic gases with energetic atoms
• Dimer-dimer collisions at finite energies in two-component Fermi gases
• Virial expansion for a strongly correlated Fermi gas with imbalanced spin populations
• The $s$-wave scattering length of a Gaussian potential
• Universality of the unitary Fermi gas: A few-body perspective
• Trapped two-component Fermi gases with up to six particles: Energetics, structural properties, and molecular condensate fraction
• Small mass- and trap-imbalanced two-component Fermi systems
• Towards Quantum Turbulence in Cold Atomic Fermionic Superfluids
• Shell-Model Monte Carlo Simulations of BCS-BEC Crossover in Few-Fermion Systems
• Trapped unitary two-component Fermi gases with up to ten particles
• Few-body resonances of unequal-mass systems with infinite interspecies two-body s-wave scattering length
• Universal Two-Body Spectra of Ultracold Harmonically Trapped Atoms in Two and Three Dimensions
• Clustering of Four-Component Unitary Fermions
• Universal few-body physics in a harmonic trap
• Lifetime of Feshbach dimers in a Fermi-Fermi mixture of ${}^6$Li and ${}^{40}$K
• Pair excitations and parameters of state of imbalanced Fermi gases at finite temperatures
• BCS-BEC crossover in a trapped Fermi super-fluid using a density-functional equation
• Surface Effects in the Unitary Fermi Gas
• Harmonically trapped Fermi gas: Temperature dependence of the Tan contact
• Cold Fermionic Atoms in Two-Dimensional Traps -- Pairing versus Hund's Rule
• On the renormalization of contact interactions for the configuration-interaction method in two dimensions
• Reduced density matrix approach to ultracold few-fermion systems in one dimension
• Finite volume effects in low-energy neutron-deuteron scattering
• Universal behavior of a trapped Fermi superfluid in the BCS-unitarity crossover
• Effective interactions and operators in no-core shell model
• The Trapped Polarized Fermi Gas at Unitarity
• Broken scale-invariance in time-dependent trapping potentials
• Few nucleons scattering in pionless effective field theory
• A general T-matrix approach applied to two-body and three-body problems in cold atomic gases
• The Contact in the BCS-BEC crossover for finite range interacting ultracold Fermi gases
• Small two-component Fermi gases in a cubic box with periodic boundary conditions
• Excitation spectrum and effective interactions of highly-elongated Fermi gas
• Analytical solution for the spectrum of two ultracold atoms in a completely anisotropic confinement
• Universality in fermionic dimer-dimer scattering
• A new effective interaction for the trapped fermi gas: the BEC-BCS crossover
• Are smooth pseudopotentials a good choice for representing short-range interactions?
• Perspectives on few-body cluster structures in exotic nuclei
• Roton in a few-body dipolar system
• On the kinetic energy of unitary Fermi gas in a harmonic trap
• Path Integral Monte Carlo study of particles obeying quantum mechanics and classical statistics
• When does a Fermi puddle become a Fermi sea? Emergence of pairing in two-dimensional trapped mesoscopic Fermi gases
• Recombination in the universal four-fermion system