Imaging the Holon string of the Hubbard model

A major direction in atomic physics today is to use neutral fermions in a lattice made of light to simulate electrons in crystals. It is hoped that such simulations will answer many long-standing questions in solid-state physics, among them the mechanism of charge transport of the 2D Hubbard model believed to capture the key physics of high-T_c superconductors. Here, we show that the imaging techniques in atomic physics enable one to visualize the highly unusual behavior of a moving hole, for which the motion of the hole generates a string, which, in turn, hinders its movement. This method allows an exact evaluation of the full charge transport at short times, which involves many interacting strings.