Recoil Effects in the Polaron Problem

Abstract

Abstract A general formalism for diagonalizing quadratic forms of boson operators [7], is used to obtain a translationally invariant variational ansatz which is suitable for calculating the polaron self‐energy, effective mass, and energy momentum relation in both coupling limits. The self‐energy and effective mass are calculated in the weak‐coupling limit. The strong coupling limit shows the wellknown α 2 ‐dependence of the self‐energy. Diagonalizing the quadratic part of the recoil term gives rise to an additional self‐energy contribution to the cutoff.