Structural properties and spin–phonon coupling effect of La1−xTexMnO3 thin films

Electron-doped La1−xTexMnO3 thin films epitaxially grown on MgO substrates by laser molecular-beam epitaxy are studied. The samples have smooth surfaces, are single crystalline, and c-oriented. Spin–glass behavior of the films is observed at low temperature. Raman spectra of the samples show a significant change in the spin–glass phase. A softening of the 615cm−1 stretching mode is observed near and below the magnetic ordering temperature. This behavior may be ascribed to magnetic interactions due to spin–phonon coupling terms.

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