| Citation | Ellen Williams’ work has significantly shaped the field of surface science through her use of brilliantly designed experiments to confront and advance theoretical and conceptual issues. Her pioneering work on the surface morphology of silicon stands as a body of ground-breaking physics that has impacted nanotechnology. In particular, the deduction of the interaction energy between steps from measured fluctuations of step morphology, and the dominant transport processes underlying the dynamics is a tour de force. By applying similar experimental rigor to the study of graphene, she established key early understanding about structural fluctuations and defect interactions in defining graphene’s properties. |