Terahertz magnetic and lattice excitations in van der Waals ferromagnet VI.sub.3./sub.

0564655 - FZÚ 2023 RIV US eng J - Journal Article
Hovančík, D. - Repček, Dalibor - Borodavka, Fedir - Kadlec, Christelle - Carva, K. - Doležal, P. - Kratochvílová, M. - Kužel, Petr - Kamba, Stanislav - Sechovský, V. - Pospíšil, J.
Terahertz magnetic and lattice excitations in van der Waals ferromagnet VI₃.
Journal of Physical Chemistry Letters. Roč. 13, č. 30 (2022), s. 11095-11104. ISSN 1948-7185
R&D Projects: GA ČR(CZ) GA21-06083S; GA MŠMT(CZ) LM2018096
Institutional support: RVO:68378271
Keywords : magnetic and structural phase transitions * magnons * phonons
OECD category: Condensed matter physics (including formerly solid state physics, supercond.)
Impact factor: 5.7, year: 2022
Method of publishing: Limited access
https://doi.org/10.1021/acs.jpclett.2c02944

We use the synergy of infrared, terahertz, and Raman spectroscopies with DFT calculations to shed light on the magnetic and lattice properties of VI3. The structural transition at TS1 = 79 K is accompanied by a large splitting of polar phonon modes. Below TS1, strong ferromagnetic fluctuations are observed. The variations of phonon frequencies at 55 K induced by magnetoelastic coupling enhanced by spin−orbit interaction indicate the proximity of long-range ferromagnetic order. Below TC = 50 K, two Raman modes simultaneously appear and show dramatic softening in the narrow interval around the temperature TS2 of the second structural transition associated with the order−order magnetic phase transition. Below TS2, a magnon in the THz range appears in Raman spectra. The THz magnon observed in VI3 indicates the application potential of 2D van der Waals ferromagnets in ultrafast THz spintronics.
Permanent Link: https://hdl.handle.net/11104/0336312