Program Highlights

Optical Control of Polarization in Hybrid 2D-Ferroelectric Structures

Alexei Gruverman, Alexander Sinitskii, and Chang-Beom Eom

Nebraska MRSEC

Switchable electric polarization of ferroelectric materials can serve as a state variable in advanced electronic systems, such as non-volatile memories and logic. Control of ferroelectric polarization by external stimuli is the key component for these systems. Nebraska MRSEC researchers have discovered an optical control of the hybrid structures comprising a two-dimensional (2D) semiconducting material, molybdenum disulfide (MoS₂), and ultrathin ferroelectric barium titanate (BaTiO₃). They showed that optical excitation of MoS₂ by ultraviolet light leads to polarization reversal in the BaTiO₃ film accompanied by a significant change in electric resistance of the hybrid structure. These findings reveal a great potential of the 2D semiconductor-ferroelectric structures for future nanoelectronic devices with optically controlled functionalities.

This research is supported by the National Science Foundation, Division of Materials Research, Materials Research Science and Engineering Program, Grant DMR-1420645.

Optically-induced polarization reversal in hybrid MoS₂/BaTiO₃ (BTO) structures: geometry of experiment (left panel) and polarization state of BaTiO₃ (right panels). The BaTiO₃ surface is partially covered with MoS₂. Under ultraviolet (UV) illumination polarization of the BaTiO₃ film underneath the MoS₂ flake is reversed as indicated by color.