Optical conductivity of colossal magnetorestistance compounds: Role of orbital degeneracy in the ferromagnetic phase

Details Optical conductivity of colossal magnetorestistance compounds: Role of orbital degeneracy in the ferromagnetic phase Optical conductivity of colossal magnetorestistance compounds: Role of orbital degeneracy in the ferromagnetic phase

1998-07-17

arxiv.org/abs/cond-mat/9807255v1

Phys. Rev. B 59, 6217 (1999)

Physics

Condensed Matter

Strongly Correlated Electrons

Revtex, 14 pages, 14 figures

Scientific paper

10.1103/PhysRevB.59.6217

Recent optical conductivity $\sigma(\omega)$ experiments have revealed an anomalous spectral distribution in the ferromagnetic phase of the perovskite system $La_{1-x}Sr_xMnO_3$. Using finite temperature diagonalization techniques we investigate $\sigma(\omega)$ for a model that contains only the $e_g$-orbital degrees of freedom. Due to strong correlations the orbital model appears as a generalized t-J model with anisotopic interactions and 3-site hopping. In the orbital t-J model $\sigma(\omega)$ is characterized by a broad incoherent spectrum with increasing intensity as temperature is lowered, and a Drude peak with small weight, consistent with experiment. Our calculations for two-dimensional systems, which may have some particular relevance for the double-layer manganites, show that the scattering from orbital fluctuations can explain the order of magnitude of the incoherent part of $\sigma(\omega)$ in the low temperature ferromagnetic phase. Moreover orbital correlation functions are studied and it is shown that $x^2$-$y^2$ orbital order is prefered in the doped planar model at low temperature.

Affiliated with

Also associated with

No associations

Rating

Optical conductivity of colossal magnetorestistance compounds: Role of orbital degeneracy in the ferromagnetic phase does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Optical conductivity of colossal magnetorestistance compounds: Role of orbital degeneracy in the ferromagnetic phase, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Optical conductivity of colossal magnetorestistance compounds: Role of orbital degeneracy in the ferromagnetic phase will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-76983