The Ge(111) surface exhibits a well-known structural transition at high temperature to a metallic phase. The transition is known to occur at about 1040 K and has been interpreted as due to the melting of the first surface layers. We have performed a new experiment with an improved high-temperature set-up which allows us to collect accurate Electron Energy Loss Spectroscopy data near the M-2,M-3 excitation edges. A probing depth of about 10 angstrom on collected EELS spectra was obtained tuning the electron gun at about 500 eV. The metalization of the surface has been clearly detected by the shift of the edge associated with the disappearance of the gap. EELS measurements, performed with a. ne temperature step and under thermal equilibrium conditions, allowed us to obtain a new determination of the transition temperature which appears to be located at T-c = 1010 K with an accuracy of about 10 K.
Melting of the Ge(111) surface probed by EELS
DI CICCO, Andrea;
2005-01-01
Abstract
The Ge(111) surface exhibits a well-known structural transition at high temperature to a metallic phase. The transition is known to occur at about 1040 K and has been interpreted as due to the melting of the first surface layers. We have performed a new experiment with an improved high-temperature set-up which allows us to collect accurate Electron Energy Loss Spectroscopy data near the M-2,M-3 excitation edges. A probing depth of about 10 angstrom on collected EELS spectra was obtained tuning the electron gun at about 500 eV. The metalization of the surface has been clearly detected by the shift of the edge associated with the disappearance of the gap. EELS measurements, performed with a. ne temperature step and under thermal equilibrium conditions, allowed us to obtain a new determination of the transition temperature which appears to be located at T-c = 1010 K with an accuracy of about 10 K.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
