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There is now a CONTENT FREEZE for Mercury while we switch to a new platform. It began on Friday, March 10 at 6pm and will end on Wednesday, March 15 at noon. No new content can be created during this time, but all material in the system as of the beginning of the freeze will be migrated to the new platform, including users and groups. Functionally the new site is identical to the old one. webteam@gatech.edu
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PhD Defense by Yiran Hu
Physics PhD Thesis Defense
Date: May 8th 2020
Time: 1:00 PM
Bluejeans: https://bluejeans.com/172026843
Committee Members:
Walter de Heer, PhD (Advisor)
School of Physics, Georgia Institute of Technology
Zhigang Jiang, PhD
School of Physics, Georgia Institute of Technology
Markus Kindermann, PhD
School of Physics, Georgia Institute of Technology
Phillip First, PhD
School of Physics, Georgia Institute of Technology
Bernard Kippelen, PhD
School of Electrical and Computer Engineering, Georgia Institute of Technology
Title: GRAPHENE ON NON-POLAR SIC FACETS
Abstract: Graphene nanoribbons (SW-GNR) grown on sidewall SiC substrate facets exhibit exceptional quantized ballistic transport over 15μm even at room temperature. For micron long ribbons, transport in these charge neutral ribbons involves a single conducting channel with a conductance of e2/h, which to this day is not fully understood. We have therefore studied here graphene grown on SiC full wafers cut along the same crystallographic orientation as the sidewall facets. We characterize graphene growth on these non-conventional (non-polar) faces and identify preferred orientation and the presence of an interface layer. Transport measurements of Hall-bar patterned graphene devices shows strong similarities with that of SW-GNR ribbons. In particular, an analysis in terms of edge and bulk electronic states reveal a ballistic edge state conduction, with mean free path larger than 10μm, and a bulk conduction with a ~10nm mean free path. Segment quantization is also discussed. The findings in this thesis point to a new route towards future large scale high-performance electronics.
