A Density Matrix Renormalization Group study of Excitons in Dendrimers

Abstract

We introduce the density matrix renormalization group (DMRG) method as an efficient computational tool for one-exciton approximations with off-diagonal disorder. This method allows us to reduce the computational effort by targetting only a few low-lying eigenstates at each statistical sampling, in contrast to the exact diagonalization methods that compute the whole spectrum. As an application of the method, we study excitons in two families of branched molecules called dendrimers using a recently introduced simple model. We compute the absortion peaks for these dendrimers varying their generation number $g$ and number of wedges $w$.