1202.3284 (Jing-Jing Wang et al.)

Absence of Wigner molecules in one-dimensional few-fermion systems with
short-range interactions    [PDF]

Jing-Jing Wang, Wei Li, Shu Chen, Gao Xianlong, Massimo Rontani, Marco Polini

We study by means of exact-diagonalization techniques the ground state of a
few-fermion system with strong short-range repulsive interactions trapped by a
harmonic potential in one spatial dimension. Even when the ground-state density
profile displays at strong coupling very well pronounced Friedel oscillations
with a `4k_F periodicity', the pair correlation function does not show any
signature of Wigner-molecule-type correlations. For the sake of comparison, we
present also numerical results for few-electron systems with Coulomb
interactions, demonstrating that their ground state at strong coupling is, on
the contrary, a Wigner molecule.

View original: http://arxiv.org/abs/1202.3284