Comparison of perturbative expansions using different phonon bases for two-site Holstein model
Abstract
The two-site single-polaron problem is studied within the perturbative expansions using different standard phonon basis obtained through the Lang Firsov (LF), modified LF (MLF) and modified LF transformation with squeezed phonon states (MLFS). The role of these convergent expansions using the above prescriptions in lowering the energy and in determining the correlation functions are compared for different values of coupling strength. The single-electron energy, oscillator wave functions and correlation functions are calculated for the same system. The applicability of different phonon basis in different regimes of the coupling strength as well as in different regimes of hopping are also discussed.
Keywords
Cite
@article{arxiv.cond-mat/9908172,
title = {Comparison of perturbative expansions using different phonon bases for two-site Holstein model},
author = {Jayita Chatterjee and A. N. Das},
journal= {arXiv preprint arXiv:cond-mat/9908172},
year = {2009}
}
Comments
24 pages (RevTEX), 12 postscript figures, final version accepted in PRB(2000) Jornal Ref: Phys. Rev. B, 61, 4592-4602 (2000)