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arXiv · 1911.04187

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

Daniel Pęcak·Tomasz Sowiński
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Abstract

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 particle-imbalanced system are studied in the framework of the noise correlation. In this way, it is shown that evident signatures of strongly correlated fermionic pairs in the Fulde-Ferrell-Larkin-Ovchinnikov state are present in the system and they can be detected by measurements directly accessible within state-of-the-art techniques. The results convincingly show that the exotic pairing mechanism is a very universal phenomenon and can be captured in systems being essentially non-uniform and far from the many-body limit.

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Daniel Pęcak, Tomasz Sowiński. 2020-03-26. Signatures of unconventional pairing in spin-imbalanced one-dimensional few-fermion systems. https://doi.org/10.1103/physrevresearch.2.012077

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