Mismatch between Raman shear modes and ferroelectric polarization in 3R-MoS 2
Researchers used Kelvin-probe force microscopy (KPFM) and low-frequency Raman spectroscopy to probe stacking order in trilayer 3R-MoS2. While KPFM could not distinguish between two neutral stacking configurations, low-frequency shear modes showed distinct fingerprints. This indicates that a combined spectroscopic and scanning approach is necessary to reliably assign sliding ferroelectric stacking orders.