On a method of treating polar-optical phonons in real space

Polar-optical phonon interactions with carriers in semiconductors are long range interactions due to their Coulombic nature. Generally, if one wants to treat these with non-equilibrium Green’s functions, this long-range interaction requires two- and three-particle Green’s functions to be evaluated by, e.g., the Bethe–Salpeter equation. On the other hand, optical phonon scattering is thought to be phase breaking, which, if true, would eliminate this concern over long-range interactions. In seeking to determine just to what extent phase breaking is important, one could treat the polar modes as a real space potential, as is done for impurities, and examine the Occurrence of any such correlations. This latter approach suffers from the condition that it is not really known how to handle the polar modes in real space—no one seems to have done it. Here, such an approach is described as one possible method.