Spin-phonon interaction and short-range order in <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msub><mml:mi>Mn</mml:mi><mml:mn>3</mml:mn></mml:msub><mml:msub><mml:mi>Si</mml:mi><mml:mn>2</mml:mn></mml:msub><mml:msub><mml:mi>Te</mml:mi><mml:mn>6</mml:mn></mml:msub></mml:mrow></mml:math>
Sanja Djurdjić Mijin, Andrijana Šolajić, Jelena Pešić, Yu Liu, C. Petrović, Michel Bockstedte, A. Bonanni, Z. V. Popović, N. Lazarević
Abstract
The vibrational properties of ferrimagnetic ${\mathrm{Mn}}_{3}{\mathrm{Si}}_{2}{\mathrm{Te}}_{6}$ single crystals are investigated using Raman spectroscopy and density functional theory calculations. Eighteen Raman-active modes are identified, 14 of which are assigned according to the trigonal symmetry. Four additional peaks, obeying the ${A}_{1g}$ selection rules, are attributed to the overtones. The unconventional temperature evolution of the ${A}_{1g}^{5}$ mode self-energy suggests a competition between different short-range magnetic correlations that significantly impact the spin-phonon interaction in ${\mathrm{Mn}}_{3}{\mathrm{Si}}_{2}{\mathrm{Te}}_{6}$. The research provides comprehensive insight into the lattice properties, studies their temperature dependence, and shows arguments for the existence of competing short-range magnetic phases in ${\mathrm{Mn}}_{3}{\mathrm{Si}}_{2}{\mathrm{Te}}_{6}$.