Infrared absorption study of charge ordered $La{}_{0.5}Ca{}_{0.5-x}S{r}_{x}Mn{O}_3$ $(0.1\le x\le 0.5$

Abstract

Infrared absorption study has been carried out on a series of half doped manganites, $L{a}_{0.5}C{a}_{0.5-x}S{r}_{x}Mn{O}_3$ $(0.1\le x\le 0.5)$, with varying magnetic ground state. The charge ordering transition observed in samples with {\normalsize $x\le 0.3$ is accompanied by a mode at $\sim 525c{m}^{-1}$ in addition to the stretching mode at $615c{m}^{-1}$ and bending mode at $400c{m}^{-1}$. Phonon hardening is found to occur below the CE - type antiferromagnetic ordering temperature. The value of the insulating gap decreases on doping with Sr from $727c{m}^{-1}$ to $615c{m}^{-1}.$}

14 pages, 5 figures, To appear in Physica B

References in corpus (7)

• Optical Evidence of Multiphase Coexistence in Single Crystalline (La,Pr,Ca)MnO3
• Charge Ordering Fluctuation and Optical Pseudogap in La${}_{1-x}$Ca${}_x$MnO${}_3$
• The Influence of A-site Ionic Radii on the Magnetic Structure of Charge Ordered La0.5Ca0.5-xSrxMnO3 Manganites
• Diffuse Neutron Scattering Study of Magnetic Correlations in half-doped La0.5Ca0.5-xSrxMnO3 (x = 0.1, 0.3 and 0.4) Manganites
• Pressure effects on the magnetic structure in La0.5Ca0.5-xSrxMnO3 (0.1 -< x -< 0.4) manganites
• Infrared absorption of the charge-ordering phase: Lattice effects
• Charge and Lattice Dynamics of Ordered State in La${}_{1/2}$Ca${}_{1/2}$MnO${}_3$: Infrared Reflection Spectroscopy Study