Semiconducting CrSBr is a layered A-type antiferromagnet, with individual layers antiferromagnetically coupled along the stacking direction. Due to its unique orthorhombic crystal structure, CrSBr exhibits highly anisotropic mechanical and optoelectronic properties acting itself as a quasi-1D material. CrSBr demonstrates complex coupling phenomena involving phonons, excitons, magnons, and polaritons. Here we show through polarization-resolved resonant Raman scattering the intricate interaction between the vibrational and electronic properties of CrSBr. For samples spanning from few-layer to bulk thickness, we observe that the polarization of the Ag2 Raman mode can be rotated by 90 degrees, shifting from alignment with the crystallographic a (intermediate magnetic) axis to the b (easy magnetic) axis, depending on the excitation energy. In contrast, the Ag1 and Ag3 modes consistently remain polarized along the b axis, regardless of the laser energy used. We access real and imaginary parts of the Raman tensor in our analysis, uncovering resonant electron-phonon coupling.
@article{arxiv.2410.22164,
title = {Raman Polarization Switching in CrSBr},
author = {Priyanka Mondal and Daria I. Markina and Lennard Hopf and Lukas Krelle and Sai Shradha and Julian Klein and Mikhail M. Glazov and Iann Gerber and Kevin Hagmann and Regine v. Klitzing and Kseniia Mosina and Zdenek Sofer and Bernhard Urbaszek},
journal= {arXiv preprint arXiv:2410.22164},
year = {2025}
}