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arXiv · 2112.13071

Raman scattering study and lattice-dynamics calculations in YTiO3: Precursor of the magnetic phase transition in the phonon anomalies

N. N. Kovaleva·O. E. Kusmartseva·A. Maljuk
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Abstract

The origin of the low-temperature ferromagnetic instability in YTiO3 driven by the interplay between lattice, orbital, spin, and charge degrees of freedom is on the background of lattice dynamics. We present a comprehensive study of temperature-dependent polarized Raman scattering in a nearly stoichiometric orthorhombic YTiO3 single crystal. The lattice-dynamics calculations authenticate the assignment for the observed Ag- and B2g-symmetry modes in terms of the atoms vibrational patterns. The obtained results suggest that trigonal GdFeO3-type distortions become unstable against tetragonal Jahn-Teller distortions, leading to the consequent orbital structure refinement and ferromagnetic ground state in YTiO3.

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N. N. Kovaleva, O. E. Kusmartseva, A. Maljuk. 2021-12-24. Raman scattering study and lattice-dynamics calculations in YTiO3: Precursor of the magnetic phase transition in the phonon anomalies. https://doi.org/10.1016/j.physleta.2022.127985

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