Photoinduced IR absorption in (La(1-x)Sr(x)Mn)(1-\delta)O3: changes of the anti-Jahn-Teller polaron binding energy with doping

TL;DR

This study investigates how photoinduced IR absorption in doped manganites reveals changes in anti-Jahn-Teller polaron binding energy, showing it decreases with increased hole doping, indicating evolving charge carrier interactions.

Contribution

It provides experimental evidence of doping-dependent variations in polaron binding energy using photoinduced IR absorption measurements in manganites.

Findings

Midinfrared peak diminishes with doping

Polaron binding energy decreases as hole doping increases

Polarons are identified as small based on peak shape

Abstract

Photoinduced IR absorption was measured in (La(1-x)Sr(x)Mn)(1-\delta)O3. A midinfrared peak centered at ~ 5000 cm$^{-1}$ was observed in the x=0 antiferromagnetic sample. The peak diminishes and softens as hole doping is increased. The origin of the photoinduced absorption peak is atributted to the photon assisted hopping of anti-Jahn-Teller polarons formed by photoexcited charge carriers, whose binding energy decreases with increasing hole doping. The shape of the peak indicates that the polarons are small.