Technical Description: This research project aims to enhance our understanding of the optoelectronic properties of strongly correlated nanostructures and to develop Mott transistors incorporating vanadium dioxide nanobeams. The project is to establish a clear physical picture of energy band alignment and carrier dynamics in the insulating and metallic phases in vanadium dioxide nanobeams. The application of scanning photocurrent microscopy (SPCM) offers spatially resolved photocurrent mapping, from which local electric field distribution and charge carrier diffusion length can be extracted. Using efficient electrochemical gating, the PI also develops Mott transistors, which take advantage of the sub-100-femtosecond phase transition for information processing. SPCM is a unique tool for identifying the gate-induced metallic layer and studying the associated interfacial junction.
Non-Technical Description: Strongly correlated materials are not only fascinating test beds for studying condensed matter physics but also have high application potential for smart windows, ultrafast optical shutters, and Mott transistors, a new type of transistors with very fast operation speeds and very low energy consumption. The spatially resolved optoelectronic investigation of vanadium dioxide nanobeams can provide key information for better understanding of the metal-insulator transitions and the development of ultrafast Mott transistors. The project involves an outreach endeavor including regular seminars on nanotechnology with a focus on K-12 public schools in low-income areas of Sacramento and Davis, California. The PI incorporates the research topics on strongly correlated nanostructures into a new interdisciplinary course.
