2025/12/09 by Kafle, Aashish, Senaratne, Ruwan, Cavazos-Cavazos, Danyel +5 · 1 citation
Materials Science · Physics and Astronomy · #Cold Atom Physics and Bose-Einstein Condensates #Electronic and Structural Properties of Oxides #FOS: Physical sciences #Organic and Molecular Conductors Research #Quantum Gases (cond-mat.quant-gas)
paper · doi:10.48550/arxiv.2512.08866
openalex publication_date 2025/12/09 · openalex created_date 2025/12/11 · openalex updated_date 2026/07/28
The low-energy excitations of a two-component repulsive Fermi gas confined to one dimension are linear dispersing spin- and charge-density waves whose respective propagation velocities depend on the strength and sign of their interaction. Quasi-1D fermions with attractive interaction realize the Luther-Emery liquid, which exhibits a rich array of phenomena, many of which are qualitatively different from those exhibited by their repulsive counterpart. We use a Feshbach resonance to access attractive interactions with 6Li atoms. We measured the spin and charge dynamic structure factors using Bragg spectroscopy and find that, contrary to repulsive interactions, the spin wave propagates faster than the charge density wave, thus producing an inversion of the classic spin-charge separation. We also find that a small spin polarization strongly suppresses the spin gap in the measured Bragg spectra. Evidence for pairing are a reduction in spin correlations with increasing attraction and RF spectra consistent with an atom/molecule mixture.