arXiv:1408.0206 · Physical Review A

Feshbach modulation spectroscopy of the Fermi-Hubbard model

Andreas Dirks, Karlis Mikelsons, H. R. Krishnamurthy, James K. Freericks

Published Nov 16, 2015• 4 citations

Abstract

In the vicinity of a Feshbach resonance, a system of ultracold atoms in an optical lattice undergoes rich physical transformations which involve molecule formation and hopping of molecules on the lattice and thus goes beyond a single-band Hubbard model description. We explore theoretically the response of this system to a harmonic modulation of the magnetic field, and thus of the scattering length, across the Feshbach resonance. In the regime in which the single-band Hubbard model is still valid, we provide results for the doublon production as a function of the various parameters, such as frequency, amplitude, etc., that characterize the field modulation, as well as the lattice depth. The method may uncover a route towards the efficient creation of ultracold molecules and also provide an alternative to conventional lattice-depth-modulation spectroscopy.

DOI: 10.1103/physreva.92.053612

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