Raman spectroscopy of phonons in Ni/CrSBr

CrSBr is a van der Waals magnet that shows quasi-1D physical behavior and is stable in the air. To realize its applications in electronic devices, it is important to understand the fundamental properties of CrSBr/metal interfaces. Polarization-resolved Raman spectroscopy was used to probe the vibrational properties of CrSBr single crystal before and after Ni thin film deposition on the CrSBr surface. By comparing Raman spectra of phonon modes from pristine bulk CrSBr and from bulk CrSBr with a thin layer of Ni on the surface, we see that the phonon modes are softened after Ni thin film deposition. First principles calculations are used to understand the phonon softening effect.