The objective of this proposal is to study the nonequilibrium hot carrier dynamics in graphene, and to explore novel graphene heterostructure devices for hot carrier optoelectronic applications. The approach is based on the integration of scanning photocurrent technique with femtosecond time-delay measurement technique. The proposal also aims to demonstrate a new type of graphene heterostructure based ultra-broadband infrared photodetector with high responsivity.
Intellectual Merit: The intellectual merit is the pioneering of graphene based hot carrier optoelectronics. The femtosecond scanning photocurrent measurement technique can be applied to other optoelectronic devices, and the investigation of hot carrier dynamics in graphene should improve the fundamental understanding of optoelectronic physics in low dimension. The hot carrier tunneling mediated photoresponse in graphene heterostructure transistors will also lead to new photodetection mechanism ideal for mid-far infrared applications.
Broader Impacts: The proposed research is highly transformative and will generate a new type of room temperature broadband infrared detector with unparalleled sensitivity. The proposal?s strong emphasis on basic science, nanoscale material, and device physics will enhance science and engineering education at both undergraduate and graduate level. The proposed outreach activities will also promote the awareness and interest in nanoscience and nanotechnology for K-12 and undergraduate students. This program will place emphasis on recruiting students from underrepresented groups. Knowledge and technologies gain from this research will be incorporated into undergraduate course revision and the development of a new graduate course focusing on carbon nanomaterials.
