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Updated: Jul 21, 2025

High Resolution Phonon-assisted Quasi-resonance Fluorescence Spectroscopy
Published on: June 28, 2016
Phonon Anharmonicity and Spin-Phonon Coupling in CrI3
Luca Tomarchio1,2, Lorenzo Mosesso1,2, Salvatore Macis1,3
1Department of Physics, Sapienza University, Piazzale Aldo Moro 5, 00185 Rome, Italy.
Abstract:
We report on the far-infrared, temperature-dependent optical properties of a CrI3 transition metal halide single crystal, a van der Waals ferromagnet (FM) with a Curie temperature of 61 K. In addition to the expected phonon modes determined by the crystalline symmetry, the optical reflectance and transmittance spectra of CrI3 single crystals show many other excitations as a function of temperature as a consequence of the combination of a strong lattice anharmonicity and spin-phonon coupling. This complex vibrational spectrum highlights the presence of entangled interactions among the different degrees of freedom in CrI3.
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