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Cooperative Jahn-Teller transition and resonant x-ray scattering in thin film ${\rm LaMnO_3}$

J. H. Song·J. H. Park·K. -B. Lee·Y. H. Jeong
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Abstract

Epitaxial thin films of stoichiometric ${\rm LaMnO_3}$ were grown on ${\rm SrTiO_3(110)}$ substrates using the pulsed laser deposition technique. From the high resolution x-ray diffraction measurements, the lattice parameters were determined as a function of temperature and the cooperative Jahn-Teller transition was found to occur at $T_{JT}$=573.0 K. Also measured was resonant x-ray scattering intensity of the orthorhombic (100) peak of ${\rm LaMnO_3}$ near the Mn K edge from low temperatures to above $T_{JT}$. We demonstrate that the integrated intensity of the (100) peak is proportional to the 3/2 power of the orthorhombic strain at all temperatures, and thus provide an experimental evidence that the resonant scattering near the Mn K edge in ${\rm LaMnO_3}$ is largely due to the Jahn-Teller effect.

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J. H. Song, J. H. Park, K. -B. Lee, Y. H. Jeong. 2001-10-29. Cooperative Jahn-Teller transition and resonant x-ray scattering in thin film ${\rm LaMnO_3}$. https://doi.org/10.1103/physrevb.66.020407

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