Scattering of a composite quasiparticle by an impurity on a lattice
Scattering of a composite quasiparticle by an impurity on a lattice
We study scattering of a composite quasiparticle, which possesses a degree of freedom corresponding to relative separation between two bound excitations, by a $\ensuremath{\delta}$-like impurity potential on a one-dimensional discrete lattice. First, we show that, due to specific properties of their dispersion, lattice excitations bind to impurities with both negative …