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arXiv · 1312.5761

Radio frequency spectroscopy of the attractive Hubbard model in a trap

Sanjoy Datta·Viveka Nand Singh·Pinaki Majumdar
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Abstract

Attractive interaction between fermions can lead to pairing and superfluidity in an optical lattice. In contrast to the `continuum', on a lattice the trap induced density variation can generate a non monotonic profile of the pairing amplitude, and completely modify the spectral signatures of any possible pseudogap phase. Using a tool that fully captures the inhomogeneity and strong thermal fluctuations, we demonstrate how the crucial radio frequency signatures of pairing are `inverted' in a trapped attractive fermion lattice compared to the traditional continuum case. These features would be central in interpreting any spectroscopic hint of fermion pairing and superfluidity.

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Sanjoy Datta, Viveka Nand Singh, Pinaki Majumdar. 2013-12-24. Radio frequency spectroscopy of the attractive Hubbard model in a trap. https://doi.org/10.1103/physreva.89.053609

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