Doublon production rate by optical lattice modulation for strongly correlated Fermionic atoms

Currently lattice modulation spectroscopy technique is applied to experiments. [1] In this spectroscopy, the number of doubly occupying atom (doublon) produced by amplitude modulation of an optical lattice potential is probed. Theoretically, it allows us to access a kinetic energy correlation function. [2] We discuss doublon excitations of strongly correlated fermionic atoms in a high-temperature regime relevant to current experiments of fermionic atoms in an optical lattice. [3] We employ a slave particle representation, and the self-energy is estimated by using non-crossing approximation based on a spin-incoherent assumption. Furthermore, this formalism is applied to calculation of the doublon production rate as a function of the lattice modulation frequency, chemical potential and temperature. Using parameters given in the experiment [1], a fit to the experimental data is implemented, and quantitatively good agreement is obtained. \\[4pt] [1] D. Greif, L. Tarruell, T. Uehlinger, R. J\"ordens, and T. Esslinger, Phys. Rev. Lett. 106, 145302 (2011).\\[0pt] [2] C. Kollath, A. Iucci, I. P. McCulloch, and T. Giamarchi, Phys. Rev. A 74, 041604(R) (2006).\\[0pt] [3] A. Tokuno, E. Demler, and T. G.iamarhi, arXiv:1106.1333.