Virtual Out-of-Plane Piezoelectric Response in MoS Layers Controlled by Ferroelectric Polarization.

The MoS carrier distribution can be controlled with the use of a dielectric environment substrate. Ferroelectric thin films are used to investigate the electrical responses at the MoS layer. The MoS/(111)-PbTiO vertical heterostructure is investigated, and the electrical responses, including piezoelectricity, are obtained using piezoresponse force microscopy. The piezoelectric response modifications obtained at the MoS layer on the ferroelectric thin films are a result of the depolarizing effect. In particular, the piezoelectricity enhancement is observed at the 19-layer MoS because of an induced dipole effect. By considering the polarization effects of ferroelectric thin films, the electrical responses at the MoS layers can be controlled, and the interfacial carrier distribution at the interface results in different electrical performances at the MoS.