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Full-Text Articles in Condensed Matter Physics
Condensation On (002) Graphite Of Liquid Bismuth Far Below Its Bulk Melting Point, M. K. Zayed, H. E. Elsayed-Ali
Condensation On (002) Graphite Of Liquid Bismuth Far Below Its Bulk Melting Point, M. K. Zayed, H. E. Elsayed-Ali
Electrical & Computer Engineering Faculty Publications
Condensation of thermally evaporated Bi on (002) graphite, at temperatures of 300-523K, was studied using in situ reflection high-energy electron diffraction (RHEED) and room temperature ex situ atomic force microscopy (AFM). For deposition at temperatures below 415±5K, transmission RHEED patterns of Bi appeared at an average thickness of ∼0.5 monolayer (ML). AFM images showed that the film consisted of crystallites in the shape of triangular step pyramids with step heights corresponding to single and double Bi layers in the [111] direction. This morphology indicates crystallization from the vapor. For deposition at higher temperatures, diffuse RHEED patterns appeared independent of the …
Time-Resolved Structural Study Of Low-Index Surfaces Of Germanium Near Its Bulk Melting Temperature, Xinglin Zeng, H. E. Elsayed-Ali
Time-Resolved Structural Study Of Low-Index Surfaces Of Germanium Near Its Bulk Melting Temperature, Xinglin Zeng, H. E. Elsayed-Ali
Electrical & Computer Engineering Faculty Publications
The structure of the low-index surfaces of germanium near its bulk melting temperature is investigated using 100-ps time-resolved reflection high-energy electron diffraction. The surface is heated by 100-ps laser pulses while a synchronized electron beam probes the structure. Ge(111)was observed to remain in its incomplete melting structure up to at least Tm + 134 ± 40 K when heated by a 100-ps laser pulse. Both the Ge(100) and Ge(110) surfaces are observed to melt near the bulk melting temperature when heated with 100-ps laser pulses. Because of the low-diffraction intensity-to-background ratio at high temperatures and because of the temperature …