Electrodynamics of Nd0.7Sr0.3MnO3 Single Crystal investigated by Optical Conductivity Analyses

TL;DR

This study examines the optical conductivity of Nd0.7Sr0.3MnO3 single crystals, revealing effects of surface treatment on measurements and highlighting the role of electron-lattice interactions in its metallic state.

Contribution

It provides new insights into how surface treatments affect optical measurements and emphasizes the importance of electron-lattice coupling in the material's optical properties.

Findings

Surface polishing distorts optical responses, especially mid-infrared.

Oxygen annealing and gold normalization improve measurement accuracy.

Spectral weight includes Drude and incoherent mid-infrared components.

Abstract

We investigated temperature dependent optical conductivity spectra of Nd0.7Sr0.3MnO3 single crystal. We found that polishing and surface scattering effects on the Nd0.7Sr0.3MnO3 crystal surfaces could significantly distort the optical responses, especially in the mid-infrared region. However, oxygen annealing and gold normalization processes seemed to remedy the distortions. We found that the spectral weight of Nd0.7Sr0.3MnO3 in the metallic state might be composed of a Drude carrier term and a strong incoherent mid-infrared absorptions. The temperature dependence of the spectral weight suggests that the electron-lattice coupling should be important in optical properties of colossal magnetoresistance manganites.