Radio frequency spectroscopy of the attractive Hubbard model in a trap

Sanjoy Datta (1, 2) , Viveka Nand Singh (3) , Pinaki Majumdar (3)

1 NEEL - NPSC - Nanophysique et Semiconducteurs
2 LPM2C - Laboratoire de physique et modélisation des milieux condensés
3 HRI - Harish-Chandra Research Institute

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.

Domaines: Physique [physics]

Sanjoy Datta, Viveka Nand Singh, Pinaki Majumdar. Radio frequency spectroscopy of the attractive Hubbard model in a trap. Physical Review A : Atomic, molecular, and optical physics [1990-2015], 2014, 89 (5), pp.053609. ⟨10.1103/PhysRevA.89.053609⟩. ⟨hal-01332893⟩