Surface optical anisotropy of GaAs(001) is extremely sensitive to adsorption of electropositive and electronegative atoms. The oxygen-induced experimental changes of the reflectance anisotropy spectrum of the As-rich surface are interpreted using ab initio calculations. We conclude that oxygen adsorption, contrary to previous beliefs, does not quench all surface-related optical transitions, but only those for which the initial state is surface-related. Alkali metal (AM) adsorption is found to induce a strong negative signal in the 3.5 eV-5 eV range, weakly dependent on surface reconstruction and AM nature, whose origin is discussed. © 2003 WILEY-VCH Verlag GmbH & Co. KGaA.
Effect of adsorption of electronegative and electropositive elements on the surface optical anisotropy of GaAs(001)
Hogan C.
Primo
;
2003
Abstract
Surface optical anisotropy of GaAs(001) is extremely sensitive to adsorption of electropositive and electronegative atoms. The oxygen-induced experimental changes of the reflectance anisotropy spectrum of the As-rich surface are interpreted using ab initio calculations. We conclude that oxygen adsorption, contrary to previous beliefs, does not quench all surface-related optical transitions, but only those for which the initial state is surface-related. Alkali metal (AM) adsorption is found to induce a strong negative signal in the 3.5 eV-5 eV range, weakly dependent on surface reconstruction and AM nature, whose origin is discussed. © 2003 WILEY-VCH Verlag GmbH & Co. KGaA.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
