Probing sliding ferroelectricity and local conductivity variation in rhombohedral MoS2

The rhombohedral (3R) phase of transition metal dichalcogenides (TMDs) such as 3R-MoS2 has attracted significant interest due to the sliding ferroelectricity induced by broken spatial inversion symmetry. To date, the intrinsic variation of local conductivity in 3R TMDs driven by polarization and stacking orders has not been fully explored. In this work, we employ optical microscopy with a bandpass filter to rapidly screen 3R-MoS2 flakes with different polarizations and piezo-response force microscopy (PFM) to confirm the presence of ferroelectric domains. Microwave impedance microscopy (MIM), a non-invasive electrical imaging tool, is utilized to visualize and quantify the local conductivity of different domains and domain walls in the samples. Our work vividly demonstrates the nanoscale conductivity variation induced by the stacking orders in 3R-MoS2, which paves the way of and tailoring device functionality based on sliding ferroelectricity.