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arXiv · 1202.3284

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

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

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.

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Jing-Jing Wang, Wei Li, Shu Chen, Gao Xianlong, Massimo Rontani, Marco Polini. 2012-02-15. Absence of Wigner molecules in one-dimensional few-fermion systems with short-range interactions. https://doi.org/10.1103/physrevb.86.075110

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