Dynamics of surface melting

Technical Report · Wed Aug 01 04:00:00 EDT 1990

DOI:https://doi.org/10.2172/6477833· OSTI ID:6477833

Elsayed-Ali, H E

The objectives of this program is to study the phenomenon of surface melting of single crystals of metals, to test for its existence, and to investigate its dynamics. Both conventional static electron diffraction and dynamic ultrafast electron diffraction are used in our study. This year, the ultrahigh vacuum facility containing the picosecond electron reflection high-energy electron diffraction system was equipped with a cylindrical mirror analyzer and a static electron gum for Auger spectroscopy. An image analysis system capable of acquiring the pulsed diffraction patterns was assembled and used in analysis of picosecond laser heated surfaces. A large set of time-resolved experiments were conducted to study the thermal response of Pb(110) to picosecond laser heating. The surface Debye-Waller effect was used to time-resolve the evolution of surface temperature. This provided us with a picosecond time-resolved surface lattice temperature probe. Results for laser fluences below surface melting show agreement with a heat-diffusion model. The temperature dependence of the Pb(100) along the (110) and the (001) azimuths using x-ray photoelectron forward scattering of the 4f{sub 7/2} core-level photoelectrons confirmed, for the first time, surface melting of Pb(100) at temperatures as low as 560 K.

• Research Organization: Rochester Univ., NY (USA). Lab. for Laser Energetics
• Sponsoring Organization: DOE/ER
• DOE Contract Number: FG02-88ER45376
• OSTI ID: 6477833
• Report Number(s): DOE/ER/45376-2; ON: DE91000978
• Country of Publication: United States
• Language: English

Related Subjects

656003* -- Condensed Matter Physics-- Interactions between Beams & Condensed Matter-- (1987-)
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
AUGER ELECTRON SPECTROSCOPY
COHERENT SCATTERING
CRYSTALS
DIFFRACTION
DOCUMENT TYPES
ELECTROMAGNETIC RADIATION
ELECTRON DIFFRACTION
ELECTRON SPECTROSCOPY
ELEMENTS
LASER RADIATION
LEAD
MELTING
METALS
PHASE TRANSFORMATIONS
PROGRESS REPORT
RADIATIONS
SCATTERING
SPECTROSCOPY
SURFACES
TEMPERATURE DEPENDENCE