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arXiv · 1803.06331

Measurement of the Dynamical Structure Factor of a 1D Interacting Fermi Gas

T. L. Yang·P. Grišins·Y. T. Chang·Z. H. Zhao·C. Y. Shih·T. Giamarchi·R. G. Hulet
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Abstract

We present measurements of the dynamical structure factor $S(q,\omega)$ of an interacting one-dimensional (1D) Fermi gas for small excitation energies. We use the two lowest hyperfine levels of the $^6$Li atom to form a pseudo-spin-1/2 system whose s-wave interactions are tunable via a Feshbach resonance. The atoms are confined to 1D by a two-dimensional optical lattice. Bragg spectroscopy is used to measure a response of the gas to density ("charge") mode excitations at a momentum $q$ and frequency $\omega$. The spectrum is obtained by varying $\omega$, while the angle between two laser beams determines $q$, which is fixed to be less than the Fermi momentum $k_\textrm{F}$. The measurements agree well with Tomonaga-Luttinger theory.

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T. L. Yang, P. Grišins, Y. T. Chang, Z. H. Zhao, C. Y. Shih, T. Giamarchi, R. G. Hulet. 2018-03-16. Measurement of the Dynamical Structure Factor of a 1D Interacting Fermi Gas. https://doi.org/10.1103/physrevlett.121.103001

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