Experimental Studies of Surface Melting and Time - Superheating of Metal Surfaces
The surface plays a very important role in the process of melting of a solid and therefore studies of the thermal behavior of surfaces can lead to a better understanding of the microscopic nature of bulk melting. In this thesis, experimental measurements of the disordering and superheating of surfaces of lead and of bismuth, respectively, are described. Surface disordering of Pb(100) is studied by monitoring the diffraction corresponding to the surface structure as a function of temperature using the x-ray photoelectron diffraction technique. The diffraction pattern gives quantitative information about the temperature-dependent degree of surface order or disorder. The Pb(100) surface is found to experience incomplete surface melting. Superheating of Bi(0001) is studied using time -resolved reflection high-energy electron diffraction, which provides surface structural information as a function of temperature as well as time. Superheating by about 90 K is observed.
- Pub Date:
- Physics: Condensed Matter; Engineering: Materials Science