Optical spectral weights and the ferromagnetic transition temperature of CMR manganites: relevance of double-exchange to real materials

Details Optical spectral weights and the ferromagnetic transition temperature of CMR manganites: relevance of double-exchange to real materials Optical spectral weights and the ferromagnetic transition temperature of CMR manganites: relevance of double-exchange to real materials

1999-08-21

arxiv.org/abs/cond-mat/9908305v1

Physics

Condensed Matter

Strongly Correlated Electrons

13 pages, 7 eps figures

Scientific paper

10.1103/PhysRevB.61.10738

We present a thorough and quantitative comparison of double-exchange models to experimental data on the colossal magnetoresistance manganese perovskites. Our results settle a controversy by showing that physics beyond double-exchange is important even in La$_{0.7}$Sr$_{0.3}$MnO$_3$, which has been regarded as a conventional double-exchange system. We show that the crucial quantity for comparisons of different calculations to each other and to data is the conduction band kinetic energy $K$, which is insensitive to the details of the band structure and can be experimentally determined from optical conductivity measurements. The seemingly complicated dependence of $T_c$ on the Hund's coupling $J$ and carrier concentration $n$ is shown to reflect the variation of $K$ with $J$, $n$ and temperature. We present results for the optical conductivity which allow interpretation of experiments and show that a feature previously interpreted in terms of the Hund's coupling was misidentified. We also correct minor errors in the phase diagram presented in previous work.

Affiliated with

Also associated with

No associations

Rating

Optical spectral weights and the ferromagnetic transition temperature of CMR manganites: relevance of double-exchange to real materials 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 spectral weights and the ferromagnetic transition temperature of CMR manganites: relevance of double-exchange to real materials, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Optical spectral weights and the ferromagnetic transition temperature of CMR manganites: relevance of double-exchange to real materials will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-116581