Phonon-modulated-hopping Polarons: X-representation Technique

Motivated by the problem of polaron effect due to phonon-modulated hopping, we formulate a generic Monte Carlo technique for solving it in the coordinate representation for both the particle and atomic displacements. The method applies to a broad class of models; the only condition is that the hopping amplitude be sign-positive. A dramatic simplification of the scheme, with the corresponding efficiency gain, takes place in models with dispersionless phonons. Our study sheds important light on the nature and universality of the most striking qualitative and quantitative effects demonstrated by the "standard" (Peierls/Su-Schrieffer-Heeger) model based on the linearized displacement-modulated hopping.