Two-flavour mixture of a few fermions of different mass in a one-dimensional harmonic trap

Abstract

A system of two species of fermions of different mass confined in a one-dimensional harmonic trap is studied with an exact diagonalization approach. It is shown that a mass difference between fermionic species induces a separation in the density of the lighter flavour independently of the number of particles. The mechanism behind the emergent separation is explained phenomenologically and confirmed by direct studies of the ground state of the system. Finally, it is shown that the separation driven by a mass difference, in contrast to the separation induced by a difference of populations, is robust to the interactions with a thermal environment.

Few strongly interacting ultracold fermions in one-dimensional traps of different shapes

“…The results for a harmonic oscillator (shown in the upper panels of Fig. 2) were recently discussed with all details in [42]. There, it was shown that along with an increasing mass ratio µ the quasi-degeneracy of the many-body spectrum is split in the limit of strong interactions.…”

“…Recently, the method has been successfully used for equal mass fermions confined in a harmonic trap [13,62,63] as well as for fermions of different masses [42]. First we decompose the field operatorsΨ σ (x) into the basis of the eigenfunctions of the corresponding single-particle Hamiltonians…”

“…However, recently it was shown that for particles confined in a harmonic trap, the mass difference between different fermionic components leads to their spatial separation if interactions are strong enough [42]. The mechanism was shown to be universal with respect to the number of particles and also very robust to external perturbations.…”

Doubly Excited Resonance States of Helium Atom: Complex Entropies

“…In particular, there has been a remarkable increase of interest in exploring properties of various quantum composite systems [2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17]. In recent years, both the entanglement and Shannon Entropy in helium and helium-like ions have also accelerated a great research attention [18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33].…”

Quantum correlations in one-dimensional Wigner molecules

“…In particular, the study of the manybody properties of various quantum composite systems is nowadays one of the most active areas of theoretical physics [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23]. Investigating quantum correlations in systems of interacting particles trapped in external potentials is not only important in view of the context of quantum information technology [24] but also a key to improving our understanding of quantum matter.…”