Understanding the coupling between lattice vibrations and magnetic order is crucial for controlling properties of two-dimensional magnetic materials. Here, we investigate the vibrational properties of bulk and thick-flake CrCl3 using polarization-resolved Raman spectroscopy, complemented by photoluminescence, photoluminescence excitation, and optical absorption measurements. Symmetry analysis, supported by first-principles phonon calculations, enables the unambiguous assignment of all eight Raman-active modes, four Ag and four Eg, previously predicted only theoretically. Excitation-energy-dependent measurements reveal that the strong enhancement of selected phonon modes originates primarily from interference effects rather than resonant Raman scattering. Temperature-dependent Raman spectroscopy further reveals pronounced signatures of spin-phonon coupling across the transition from a fully antiferromagnetic phase, through an intermediate regime with local, domain-like ferromagnetic order, to the paramagnetic phase, accompanied by a clear rhombohedral-to-monoclinic structural transition. Together, these results demonstrate how lattice, electronic, and magnetic degrees of freedom collectively govern the Raman response of CrCl3.
@article{arxiv.2601.16927,
title = {Strong Spin-Lattice Interaction in Layered Antiferromagnetic CrCl$_\textrm{3}$},
author = {Łucja Kipczak and Tomasz Woźniak and Chinmay K. Mohanty and Igor Antoniazzi and Jakub Iwański and Przemysław Oliwa and Jan Pawłowski and Meganathan Kalaiarasan and Zdeněk Sofer and Andrzej Wysmołek and Adam Babiński and Maciej Koperski and Maciej R. Molas},
journal= {arXiv preprint arXiv:2601.16927},
year = {2026}
}