Optical conductivity of doped Mott insulator: the interplay between correlation and electron-phonon interaction

Giulio Dr. de Filippis (1) , Vittorio Cataudella (1) , Andrey Dr. Mishchenko (2) , Carmine Dr. Antonio Perroni (1) , Naoto Nagaosa (2)

1 CNR-INFM Coherentia - CNR-INFM Coherentia and Dip. di Scienze Fisiche
2 CMRG - Cross-Correlated Materials Research Group

The optical conductivity (OC) of cuprates is studied theoretically in the low density limit of the t-t'-J-Holstein model. By developing a limited phonon basis exact diagonalization (LPBED) method capable of treating the lattice of largest size 4x4 ever considered, we are able to discern fine features of the mid-infrared (MIR) part of the OC revealing three-peak structure. The two lowest peaks are observed in experiments and the highest one is tacitly resolved in moderately doped cuprates. Comparison of OC with the results of semianalytic approaches and detailed analysis of the calculated isotope effect indicate that the middle-energy MIR peak is of mostly magnetic origin while the lowest MIR band originates from the scattering of holes by phonons.

Mots clés: Cuprates; Optical conductivity; strongly correlated electrons; electron-phonon interaction

Domaines: Electrons fortement corrélés [cond-mat.str-el]

Giulio Dr. de Filippis, Vittorio Cataudella, Andrey Dr. Mishchenko, Carmine Dr. Antonio Perroni, Naoto Nagaosa. Optical conductivity of doped Mott insulator: the interplay between correlation and electron-phonon interaction. 2009. ⟨hal-00400458⟩