Charge dynamics in magnetically disordered Mott insulators

With the aid of both a semianalytical and numerically exact method, we investigate charge dynamics in vicinity half-filling one- two-dimensional $t\text{\ensuremath{-}}J$ model derived from Fermi-Hubbard limit large interaction $U$ hence small exchange coupling $J$. The spin degrees freedom are taken to be disordered. So consider $0<J\ensuremath{\ll}T\ensuremath{\ll}W$, where $W$ is bandwidth. We focus on evaluating local spectral density single hole excitation gap that separates upper lower Hubbard band. find indications no band edges exist if magnetic into account; instead edges, Gaussian tails seem appear. A discussion underlying physics provided.