Pairing in a system of a few attractive fermions in a harmonic trap

  title={Pairing in a system of a few attractive fermions in a harmonic trap},
  author={Tomasz Sowi'nski and Mariusz Gajda and Kazimierz Rzążewski},
  journal={Europhysics Letters},
We study a strongly attractive system of a few spin-(1/2) fermions confined in a one-dimensional harmonic trap, interacting via two-body contact potential. Performing exact diagonalization of the Hamiltonian we analyze the ground state and the thermal state of the system in terms of one- and two-particle reduced density matrices. We show how for strong attraction the correlated pairs emerge in the system. We find that the fraction of correlated pairs depends on temperature and we show that this… 

Unconventional pairing in one-dimensional systems of a few mass-imbalanced ultracold fermions

We study the ground-state properties of a two-component fermionic mixture effectively confined in a one-dimensional harmonic trap. We consider scenarios when numbers of particles in components are

Many interacting fermions in a one-dimensional harmonic trap: a quantum-chemical treatment

We employ ab initio methods of quantum chemistry to investigate spin-1/2 fermions interacting via a two-body contact potential in a one-dimensional harmonic trap. The convergence of the total energy

Analytical and numerical studies of Bose–Fermi mixtures in a one-dimensional harmonic trap

In this paper we study a mixed system of bosons and fermions with up to six particles in total. All particles are assumed to have the same mass. The two-body interactions are repulsive and are

Unconventional pairing in few-fermion systems tuned by external confinement

We study the ground-state properties of a two-component one-dimensional system of a few ultracold fermions with attractive interactions. We show that, by ramping up an external potential barrier felt

Ground-State Magnetization in Mixtures of a Few Ultra-Cold Fermions in One-Dimensional Traps

Ground-state properties of a few spin- 1 / 2 ultra-cold fermions confined in a one-dimensional trap are studied by the exact diagonalization method. In contrast to previous studies, it is not

Few-to-many particle crossover of pair excitations in a superfluid

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

Signatures of unconventional pairing in spin-imbalanced one-dimensional few-fermion systems

A system of a few attractively interacting fermionic $^6$Li atoms in one-dimensional harmonic confinement is investigated. Non-trivial inter-particle correlations induced by interactions in a

Slightly Imbalanced System of a Few Attractive Fermions in a One-Dimensional Harmonic Trap

The ground-state properties of the two-flavored mixture of a few attractive fermions confined in a one-dimensional harmonic trap is studied. It is shown that for slightly imbalanced system the

Canonical pair condensation in a flat-band BCS superconductor

The standard approach of the Bardeen–Cooper–Schrieffer (BCS) theory of superconductivity is to introduce a self-consistent mean-field approximation, and a variational ansatz for the many-body ground

Comparing models for the ground state energy of a trapped one-dimensional Fermi gas with a single impurity

We discuss the local density approximation approach to calculating the ground state energy of a one-dimensional Fermi gas containing a single impurity, and compare the results with exact numerical



Fermionization of two-component few-fermion systems in a one-dimensional harmonic trap

The nature of strongly interacting Fermi gases and magnetism is one of the most important and studied topics in condensed-matter physics. Still, there are many open questions. A central issue is

Pairing in few-fermion systems with attractive interactions.

From the tunneling time scales, this work infer the differences in interaction energies of systems with different number of particles, which show a strong odd-even effect, similar to the one observed for neutron separation experiments in nuclei.

Few interacting fermions in a one-dimensional harmonic trap

We study spin-1/2 fermions, interacting via a two-body contact potential, in a one-dimensional harmonic trap. Applying exact diagonalization, we investigate their behavior at finite interaction

Elementary excitations of a two-component Fermi system using the atomic-orbital approach

We investigate the ground state properties of normal and superfluid phases of a mixture of Fermi atoms at zero temperature in a quasi-one-dimensional harmonic trap. Assuming pairing occurs in the

Universal quantum behavior of interacting fermions in one-dimensional traps: From few particles to the trap thermodynamic limit

Dip. di Fisica dell’Universita di Pisa and INFN, Largo Pontecorvo 3, I-56127 Pisa, Italy(Dated: January 16, 2014)We investigate the ground-state properties of trapped fermion systems described by the

Spectroscopy for a Few Atoms Harmonically-Trapped in One Dimension

Spectroscopic labels for a few particles with spin that are harmonically trapped in one-dimension with effectively zero-range interactions are provided by quantum numbers that characterize the

Dynamics and decoherence of two cold bosons in a one-dimensional harmonic trap

We study dynamics of two interacting ultracold Bose atoms in a harmonic oscillator potential in one spatial dimension. Making use of the exact solution of the eigenvalue problem of a particle in the

Fermionization of two distinguishable fermions.

By adding more particles the authors' system can be used as a quantum simulator for more complex systems where no theoretical solution is available, and good agreement between experiment and theory is observed.

Pairing fluctuations in trapped fermi gases.

A parity effect is predicted, i.e., that pairing fluctuations show a maximum or a minimum at the center of the trap, depending on the value of the last occupied shell being even or odd.

Exact solution for infinitely strongly interacting Fermi gases in tight waveguides.

It is shown that the total ground-state density profile behaves like the polarized noninteracting fermions, whereas the spin-dependent densities display different properties for different spin configurations.