Bose-Hubbard model with localized particle losses

We consider the Bose-Hubbard model with particle losses at one lattice site. For the noninteracting case, we find that half of the bosons of an initially homogeneous particle distribution are not affected by dissipation that only acts on one lattice site in the center of the lattice. A physical interpretation of this result is that the surviving particles interfere destructively when they tunnel to the location of the dissipative defect and therefore never reach it. Furthermore we find for a one-dimensional model that a fraction of the particles can propagate across the dissipative defect even if the rate of tunneling between adjacent lattice sites is much slower than the loss rate at the defect. We analyze the robustness of our findings with respect to small interactions and small deviations from the symmetric setting. A possible experimental realization of our setup is provided by ultracold bosonic atoms in an optical lattice, where an electron beam on a single lattice site ionizes atoms that are then extracted by an electrostatic field.